When Mac, a shy 8-year-old boy, is forced to give up his imaginary friend, Bloo, he finds the perfect place for him: Foster's Home for Imaginary Friends. There, they meet many of the home's residents, like Eduardo, Wilt and Coco; as well as the home's staff. Their problems appear to be solved until it is revealed that Foster's is an foster home and adoption center, and, if Mac isn't there at the time someone tries, another person could adopt Bloo. To make matters worse, a sinister plot by the evil imaginary friend Duchess, uses Mac's 13-year-old bully brother, Terrence, and puts Bloo in peril. Now Mac and his new friends from Foster's must work together to save Mac's best buddy Bloo.
When Mac, a shy 8-year-old boy, is forced to give up his Imaginary Friend, Bloo, he finds the perfect place for him: Foster's Home for Imaginary Friends. There, they meet many of the home's residents, like Eduardo, Wilt and Coco; as well as the home's staff. Their problems appear to be solved until it is revealed that Foster's is an adoption center, and, if Mac isn't there at the time someone tries, they could adopt Bloo. To make matters worse, a sinister plot by an evil Imaginary Friend uses Mac's 13-year-old bully brother, Terrence, and puts Bloo in peril. Now Mac and his new friends from Foster's must work together to save Mac's best buddy Bloo.
It's Madame Foster's birthday and Frankie has forgotten the one thing necessary for any party, the streamers! As Mr. Herriman orders her to go get some, Bloo, Eduardo, Mac, Wilt, and Coco tag along as well. They have five minutes left until they can leave, so they stop a one store and Frankie falls asleep in a vibrating chair and when she wakes up, everyone left to different places. Will Frankie be able to get to the party in time?
Bloo finds out about a door in the home that everyone is forbidden to open. As he asks around about the door, no one tells him what is inside of it. However, in the middle of the night, Bloo manages to sneak to the door and open it, but will he like what he has found or will his deeds cause untold trouble?
Mr. Herriman isn't happy about Bloo being able to stay at the home indefinitely, and is getting on the little guy's case about the rules of the house. Unfortunately, when Bloo learns that Mr. Herriman will have him ejected from the home if he doesn't toe the line, Bloo gets so stressed out that he accidentally breaks a statue of Madame Foster! Bloo and his buddies will have to fix the "busted bust" before Mr. Herriman finds out and has Bloo thrown out on the street.
When Mac visits Foster's, Bloo wants to show him something up on the roof, though when it's time for them to go back downstairs, they find themselves lost and unable to get downstairs. With Bloo becoming unstable due to hunger and Mac potentially getting in more and more trouble with each passing minute, will they manage to find their way back down before it's too late?
Mac and Bloo are using Frankie's digital camera to make video interviews for the new Foster's website, when they stumble upon Mr. Herriman indulging Madame Foster's whims and doing a little dance for her. Much to Mac's chagrin, not only do Bloo and Frankie show the embarrassing footage to almost everyone in the house, but Bloo uploads the film to the Internet. It won't be long before Mr. Herriman discovers he's become the latest Internet fad, and you can bet he won't be happy!
As a new day begins at Foster's, with everyone enjoying their favorite television program, The Loved and the Loveless, a new friend named Berry enters the house as sweet as can be, though with one glance on Bloo became love struck and determined to make Bloo love her back, though there is one thing that truthfully stands between her and Bloo, and that is Mac. When Mac and Bloo are trying to win a world record, Berry gets mad. After many schemes to try to get rid of Mac, Berry tries to tell Bloo that Mac is stopping him from winning the world record. When Bloo says that to Mac, he gets mad and dosen't want to break a world record anymore. But Berry makes Bloo the almost world's largest rubber band ball and both of them will put the last rubber band to make it the biggest. Meanwhile, Mac is running to Foster's so Bloo and Mac can put on the last rubber band, but will Mac get there in time before Berry and Bloo put on the rubber band?
Terrence has an idea to make up a friend named Red to beat Bloo and Mac up with, though the friend he creates doesn't seem to be capable of comprehending the task it was given. Will Red serve Terrence as he was created for, or will it choose it's own path and disregard what Terrence ordered him to do?
Bloo is jealous of Wilt getting special attention for the number of abandoned imaginary friends he brings to Foster's, so he tries to rescue imaginary friends just like Wilt does. When Bloo finds a man in a cell-phone suit and thinks he is a friend, he takes him to Foster's, thinking everyone will give him more praise than they give Wilt.
After Eduardo finds a puppy when he was taking out the trash, he decides to keep it, despite the fact that dogs are not permitted inside the house. However, despite Eduardo's best efforts, the dog gets loose and starts causing problems that Eduardo takes the blame for in fear of the puppy being found out. Will Eduardo manage to keep the puppy without Mr. Herriman finding out, or will the puppy be forced to leave due to Mr. Herriman's strict policy against dogs?
It's Adopt-A-Thought Saturday, an event that focuses on getting good friends adopted on the weekends when children are out of school. But Mac and Bloo find out after their good friend Jokey gets adopted. While the event is usually a good thing for both imaginary friends and those seeking to adopt them, Bloo doesn't want his friends to be adopted, so he works with Mac to try to find a way to put an end to the event. From atracting friends in the house with scented cupcakes to dropping plastic spiders, they try as many plans as they can. Will they be successful in prevent the adoption of their friends, or are their best efforts in vain?
Bloo and Mac enjoy playing with each other in the mud while raining, but sometimes there can be consequences. As Mac and Bloo get sick, causing Bloo to turn white and Frankie to take Mac home, Bloo misses out on the scary movie the friends planned to watch that night. However, the movie scares the friends enough that they believe that the ghost is real, and they mistake Bloo to be the ghost. Will they be able to figure out it's him before they end up hurting Bloo or themselves in the process?
Frankie and Madame Foster are leaving for a while, so Mr. Herriman is placed in charge of the house. However, Madame Foster inadvertently gives Bloo the idea to throw a wild party, and he plans to do so without Mr. Herriman's consent. While they manage to come up with a method to distract Mr. Herriman, there is still one person that could stop the party, and that's Mac, though Bloo knows that with a little bit of sugar, Mac can be placed under control, or so he thinks.
Mac drafts the gang onto Madame Foster's bowling team to help her beat her arch-rival, Jerkhins. But when Mac gets booted off his own team, he must learn the ways of the ball from a bowling guru. Meanwhile, Bloo is the best player on Foster's team, but the other team steals him by offering him a paddleball if he wins for their team. When Mac is done with his bowling lessons by the bowling guru, he comes back to Foster's team. Will Mac be good enough to beat the other team which now has Bloo or will he mess up and lose?
Where There's a Wilt There's a Way: All Wilt wants to do is watch his favorite basketball game on TV, but the house's ridiculous requests and Wilt's ridiculous inability to refuse them threaten to keep him from the big game.
A new imaginary friend has come to Foster's, but he keeps misbehaving all around the house. All other imaginary friends are taking the blame. That is, until Bloo comes up with his master plan!
When Ivan, a seeing eye friend, loses his blind kid, the friends try to find the boy before harm comes to the seeing eye's creator.
Mac takes Bloo to school for show and tell. The kids love Bloo so much, that they imagine Bloos themselves. Tons of Bloos are created, and Bloo dubs them his brothers and himself leader, but will Bloo take it too far?
When Foster's needs a new roof, Bloo bakes up a plan to sell Madame Foster's amazing cookies after his first attempt at selling lemonaid int he middle of winter failed. When they finally get enough money to buy a new roof, Bloo gets a "little" carried away and wants to become rich and make all the imaginary friends his servants! Will Bloo's business plan work, or will his treatment of the friends make his sweet success turn sour?
Mac develops a crush on Frankie when she said that she loved him for doing her paper work and kisses him. Later, Bloo develops a crush on Frankie too and Mac and Bloo compete for her love. But when Frankie suddenly starts professing her love for an unnamed suitor, Mac and Bloo become jealous and try to thwart every guy she comes in contact with, namely Chris (a pizza guy), Prince Charming (an imaginary friend), and her real date, Dylan who takes her to a fancy restraunt for their date. Will Bloo, Mac, Chris, and Prince Charming win her love?
One morning, Mac wakes up to find that he's unintentionally created another imaginary friend named Cheese. Madame Foster allows the same rules as there are for Bloo, but Bloo does not approve of his new brother. After many attempts to get rid of him, Cheese disappears on his own. Bloo realizes that Foster's could be a very dangerous place for one so stupid as Cheese. Can he find him before something happens or Mac notices Cheese is missing?
The gang goes an arcade and everyone's winning lots of tickets except Bloo. Bloo then becomes very interested in a prize that's 500 tickets: glow in the dark Dracula teeth. So Bloo wants them to give them their tickets so he can get one, but the others decided to collect all of their tickets and get a rubber elephant, which Bloo grows an obsession with later on. But when Frankie, who's holding the rubber elephant, goes to sleep, Bloo sneaks in and steals it. When he's playing with, it breaks. The only option is to go to the arcade and win 500 tickets to get another rubber elephant. Can he get the elephant before the others find out?
Bloo has a reputation for being a funny imaginary friend, though his jokes sometimes offend people. When Bloo cracks a joke about a new imaginary friend's height, the new guy challenges him to meet him outside at 4 o'clock. Will Bloo manage to find a way to dodge the challenge or will he have to face the consequences of his joke and possibly be severely injured?
When Bloo becomes jealous of Eduardo and the other friends for appearing on TV, he pretends to be a very sick friend in order to appear, despite the fact that it is only for friends up for adoption. A Hollywood agent named Kip Snip soon turns him into a star, but starts to treat him badly and won't let him see Mac. When Bloo tries to quit, he is informed that he signed adoption papers and has no choice in the matter. Can Mac and Bloo ever be re-united?
After beating Mac's high score in a video game, Bloo goes to rub it in his face at school. But he is horrified when he comes to the conclusion that Mac is a nerd. When Mac arrives, Bloo quickly works to make Mac cool, but none of their ideas work. But just as Mac says he doesn't care about being cool, the coolest kid in the school, Jamez Withazee tells him that the fact that he doesn't want to be cool, makes him cool, and invites him to 'The Rock.' As Mac is not at Foster's at 3 o' clock because Jamez tells him that Foster's is for nerds, Mr. Herriman is very quick to ensure that Bloo gets adopted. Now Bloo must find Mac, while at the same time avoiding adoption! Will bloo find Mac before he gets adopted?
During the production of the home's newspaper, a new friend returns to Foster's. Well, not new, but very old indeed. In fact, it just so happens that it's Uncle Pockets, the very first imaginary friend to come to Foster's. Uncle Pockets' charm drives all the other friend's attentions to him, making Bloo jealous. Bloo then decides to try and expose Uncle Pockets as a fraud through the home's newspaper. Then later, when he thinks he hears that Uncle Pockets is trying to kill Mr. Herriman, Frankie, and Madame Foster, he stops at nothing to stop him before it's too late!
A rich benefactor is considering giving money to a charity, and visits Foster's to see if it is worthy. Mr. Herriman gets Mac and Bloo to keep Coco out of the way but in the end it is only when the benefactor mistakes Coco as Mr. Herriman's wife that he considers Foster's, and invites them to his mansion where he will decide which charity gets the money. Mr. Herriman then tries to teach Coco to be sophisticated, while Mac and Frankie teach Bloo sarcasm, since he didn't understand that Mr. Herriman was being sarcastic when he promised them two jet cars. At the mansion it is a competiton to see who will win the money. Can Coco and Mr. Herriman win the money for Foster's? And what about Mac and Bloo who enter as 'Jet Cars for Tiny Tots'?
Eduardo runs away from the home to prove that he's not a coward. Meanwhile, Terrence is looking for an imaginary friend to compete in the Extreme-O-Saur Battle, and he comes across Eduardo. Terrence uses him to fight against huge imaginary friends at the dumpster. Mac, Bloo, Wilt, and Coco must search for Eduardo.
Richie Wildebrat, a kid at Mac's School, keeps braging about his imaginary friend, Blake Superior, and he keeps bragging about him winning the imaginary friend talent show pageant. Mac wants to beat him so it can end Richie's bragging, so he asks Bloo to enter in the pageant, but Bloo doesn't want to, then he gets the hiccups, which Blake says is ridiculous, so Bloo enters. How is Bloo going to beat Blake Superior with his hiccups?
Mac and Bloo ask Mr. Herriman to go camping out in the wilderness. Madame Foster thinks it is a great idea to get away from all the civilization for a while, but when Bloo eats all of the food on a camping trip, everyone struggles to survive. Adversity sets in as Mr. Herriman encounters real bunnies, Madame Foster fights against a bear, Wilt gets stuck in quicksand, Coco has trouble casting a live fish, and Eduardo feels upset about Mac and Bloo trying to hunt the animals down for food. Will they ever make it out in one piece?
Goofball John McGee comes to Foster's, who is a total pain. Frankie thinks he's a teenage kid passing himself off as a imaginary friend, who always needs help on homework, needs to wash his jerseys, and eats all the food that Frankie bought from the store, but everyone else believes otherwise. So now, Frankie is out to prove him as a fraud. But is he really the fraud Frankie thinks he is?
Duchess is adopted by Mac's neighbors, and Foster's doesn't want to take her back. Meanwhile, Terrence told Mac that his mom is thinking about moving to Singapore. It's up to Mac and Bloo to get rid of Duchess. They try to frame Duchess for what they did to their home, but it only makes the family love Duchess even more. Mac and Bloo have no choice but to return her back to Foster's. However, Terrence decides to help the others back at Foster's Home to keep Duchess away.
Mac enters a contest to win a trip to Europe. But when the gang tries to pack at the last second, everyone has delays that keep the gang from going. While at the same time, Mac is getting more upset. Will Mac and his friends be able to make their flight to Europe on time?
After Mac bumps into a girl named Goo when he gets something out of a tree, she thinks that Mac is her boyfriend, and Goo begins visiting Mac everyday at Foster's. With her hyper active imagination, she creates a new friend one after another, which causes a big problem for the other imaginary friends in the house. After she creates so many imaginary friends that it crowds the whole house, the others have to sleep in the Foster's bus. Can Mac stop Goo from creating so many friends?
Mr. Herriman becomes addicted to carrots. Meanwhile, Bloo tries desperately to avoid eating Frankie's "it" by doing bad things, but Mr. Herriman ignores or misinterprets the bad deeds and sends everyone else to bed with no supper instead. Also, Frankie learns to cook "it" under the guiding (and painful) wooden spoon of Madame Foster.
When Eduardo gets fleas while getting one of the house’s imaginary puppies to take a bath, he becomes discontent as the fleas are driving him mad. However, despite the way he feels, he decided to keep the fleas on him because he believe they’re his friends; though Frankie and Mr. Herriman want none of it and they decide to go to drastic lengths to get the fleas removed. Meanwhile, Bloo wants to get some fleas of his own and he does anything possible in order to attempt to get Eduardo to share them.
When a hoard of imaginary Santas enter the house, Mac starts to believe that there is no such thing as Santa Claus. Bloo decided to try to prove him wrong, in hopes of getting the real Santa to deliver him more presents, so they go about trying several experiments that would logically prove Santa is real. Will Mac be able to regain his faith in Santa Claus or will this be the worst Christmas ever for Foster’s and Mac alike?
Mac makes a home movie about Foster's Home for his school project, but Bloo edits it into a blockbuster hit. This leads him to be entered in the state student film festival. With Bloo's help, they make T-Rexatron III Alien Wolfhound, A Prequel In Time: The Unrelenting. Eduardo, though, thinks he has a problem breaking wind when it was Bloo doing sound effects and doesn't want to be in Bloo's movie which forces Bloo to make him to a computer animated character in his movie. What happens at the wrap party and how will the movie turn out?
Everyone in Fosters is sick of Herriman's rules, so Frankie decides that she shoud run for president. Bloo hears about this and decides to take an oppurtumity. Bloo seems to have the most chances of winning but Frankie tells them that she helped them every day. Frankie now is having the upper and but Herriman might have a trick under his rabbit sleeve. Who will win in the end: Franke, Bloo,or Mr. Herriman?
When a recent adoption leaves a room at Foster's vacant, Bloo, Coco, Wilt, and Eduardo all fight over it, along with another friend named Peanut Butter. Everybody soon starts to make contests to see who will win the room, which leads Bloo to try to make contests that he can cheat at. how will they settle this fight and who will win the room?
When Mac taks his classmates on a field trip to Foster's, everybody loves Coco and Bloo wants all the attention after Coco lays eggs with imaginary friend trading cards. Soon, when Bloo throws eggs at everyone, they run away and now Coco hates Bloo. When all the friends start trading and collecting the cards, soon Bloo gets intrested and starts to collect them all. Will Bloo collect all of them without Coco's help?
When a large and dangerous imaginary friend is destroying the city, Imaginary Man comes and saves the day, and now, Mac is a fan. But once Mac is his sidekick, Bloo is jealous and joins forces with Nemesis, Imaginary Man's mortal enemy. Will justice or evil win in the battle of the superfriends?
The residents prepare for the annual house photo. Meanwhile, Bloo and Mac search for an answer behind a weird photo of Foster's taken years ago, Eduardo gets an "extreme makeover" from Duchess that surprises the other residents, Coco realizes she needs to lose weight and Wilt has trouble being in the house photo without getting his head cut out from the banner.
When the friends go out to the beach and leave Bloo in the house alone on purpose so that he doesn't ruin the fun, he and Mac try to squeeze in as much fun as possible and make it the best day of their lives, but are they bringing the house down?
Old Man Rivers, who lives across the street from Foster's hates imaginary friends, and on "Adopt-A-Thought Saturday", his grandson, Young Man Rivers, torments Bloo. Meanwhile, Bloo and Madame Foster throw papers - that are adoption forms - at Old Man Rivers, who keeps them for himself. What will happen?
Bloo and the gang arrive at Mac's house for slumber party that Mac didn't plan to have on a school night. But because they are all so loud, Mac's Mom could wake up and get them all into trouble. Will the slumber party be a success or a failure?
Bloo, along with the rest of the Imaginary Friends (besides Edwardo) and Frankie, plan a surprise party for Mac. However, Mac wants no part of it.
Bloo notices after a trip to the grocery store that Frankie has left the keys in the bus, and decides to take Mac for a joyride in the Foster's bus, and Wilt promises to keep it a secret. Both Bloo and Mac get lost, and now Wilt has ke keep it a secret from Frankie while telling off Eduardo (who wants to buy a mattress at half off), Coco (who feigns illness) and Mr. Herriman as well as Goo, who creates a Mr. Herriman who speaks jibberish, a Mac look-alike with a spotted tongue and a Japanese-speaking Blooregard. When Frankie get suspicious about the missing bus, can Wilt keep his secret safe?
Foster's is being put on TV, and Frankie wants everything perfect. Meanwhile, Cheese keeps appearing at Foster's, even after being told numerous times that he doesn't live there. So, in an attempt to keep him out, Mr. Herriman installs a security system. Unfortunetly, due to misreading the directions, nobody knows the password except for Cheese, who saw Herriman input the code. But everything the gang tries to get the password out of Cheese fails, and the news crew is only around the corner. Can the gang succeed and get the password out of Cheese?
Bloo announces that a one-eyed cat-like imaginary friend is in trouble. No one wants to help him at first because it might be a trick, but Madame Foster forces Frankie, Coco, Wilt, and Eduardo to help him. They find that the imaginary friend is stuck in a tree and Bloo tries to help by climbing on top of them. Instead of helping, they fall and Frankie yells at Bloo. Madame Foster pitches in and using a large brown stick, she gets up there and rescues the friend. Now, reporters from a news network arrive at the scene and acknowledges Madame Foster. Bloo whines that he does do good deeds all the time, so he waxes the floor (everyone who walks on it slides and injures themselves) to prove his point. Since he filmed himself, he sends the tape to a news channel. Instead of congratulating Bloo, he actually becomes embarrassed. Bloo tries another tactic to prove that he can do good deeds: building another home for imaginary friends called Bloo's Foster's Home for Imaginary Friends.
When a pen that looks like Abraham Lincoln is caught with a student cheating on a test by Mac's teacher, he is saved by Mac and Blooregard along with his au pair, a green ogre type. The Lincoln pen cons Madame Foster into a new plan to adopt an overcrowded home to unsuspecting adoptors for a fee, then take over the house and plan to turn the home into a casino. Mac finds this out the hard way as Wilt becomes a flagpole and Eduardo becomes a shell of his former self, as it were, and is put with Mr. Herriman and Frankie in a locked closet. What will Bloo do to save the house, and will Madame Foster get control of the house back?
In her sleep, Goo accidentally creates all the villain characters from a make believe game that she had helped out on while the power was out at the home during a thunderstorm, who then imprison Mac and Bloo at the home. Now, the gang must finish the game to save their friends.
It's time for the Five Year Creator Reunion Picnic, where imaginary friends' creators come to Foster's to see their imaginary friends. However, once again, Wilt's creator doesn't show up. So he sets off on a cross-country journey to find his creator. But soon Mac and the gang find out that Wilt had gone missing and set out on a road trip to find him. But Bloo's ridiculous theories of to Wilt's disappearance leads to many twists and turns in the journey to find Wilt. Will Wilt ever find out why his creator doesn't show up? Will Mac and the gang find Wilt? Will the lot make it out in one piece?
Blooregard is convinced that Cheese looks like an alien after watching a sci-fi movie about brain-eating spacemen and reading a tabloid newspaper with a picture that has an alien that looks like him, so he sends a message to outer space in essence inviting them to Earth.
When the Fosters gang goes to a swap meet, Edwardo gets his hands on a $100 bill after a thief loses it. Everyone gets greedy and they want the bill causing chaos.
Bloo goes with Madame Foster in a hurry, thinking that they'll join the rest of the crew at the annual county fair, but that shortcut finds both Blooregard and Madame Foster at a fabric store.
After visiting a retirement home, Blooregard wants to leave Madame Foster's and move there. To do that he takes a bath long enough to be all pruned.
Bloo tells Mac an outlandish story.
Bloo and the gang try out as a rock and roll band.
Blooregard believes that Mac, even at his age, is getting married.
Bloo befriends a rich kid named Barry Bling, heir to a paddleball fortune, but things don't seem what they ought to be for Mac.
Tickets won in a radio contest cause a rift between Mac, Bloo, and Frankie
Blooregard plans to play the ultimate trick on Halloween after tying down Mac onto a bed preventing another sugar rush, but when things go awry, most of the main characters of the residence turn into zombies.
When Eduardo tells little white lies to those at the nursery, including a little child named Scrappy that admires Eduardo, he has to cover them up before they catch up to him.
A retelling of "The Big Cheese" from the view of a little pea, who against all odds, helps Frankie turn a negative into a positive.
A plan to have Mr. Herriman mellow out backfires as conditions at the home deteriorate.
Mac asks Jackie Khones to help him see who took his library card and took out a book from the library and having it be overdue.
Coco escapes from Foster's and goes on a wild adventure.
When termites run amok at Fosters, Mr. Herriman rents out a hotel for the duration and a prank war ensues between Bloo and Coco.
When a field trip to a water park is cancelled because of rain, the gang decides to upload videos to the internet.
A 30-mile trip back to Foster's from the Prize Hive turns into an outrageous race with viewers deciding the winner online at cartoonnetwork.com by playing "Big Shot Checkers" between May 19th, 2008 and the original airdate of May 29th, 2008.
A 30-mile trip back to Foster's from the Prize Hive turns into an outrageous race with viewers deciding the winner online at cartoonnetwork.com by playing "Big Shot Checkers" between May 19th, 2008 and the original airdate of May 29th, 2008. This is the alternate version released online where Bloo wins the race instead of Mac.
In the sequel to "The Bloo Superdude and the Magic Potato of Power", our hero (Bloo) must set out on a quest if he wishes to attend a ceremony honoring The Great Creator of Everything (Mac). In reality, Bloo is sick and hallucinating, making him think he's the Superdude when he's only running around the house. A delirious Bloo tries to get out of the house to get to Mac's birthday party outside.
A little dare between Mac and Bloo turns into a huge daring competition between the house members once Madame Foster gets involved.
Bloo is sad about Eduardo getting adopted and holds auditions to get an alternate one; meanwhile, the residents get letters from those that were adopted in another Adopt-a-Thought Saturday.
Frankie and Mr. Herriman are hosting an important party in the foyer to raise funds for the house, so Frankie tells Bloo, Wilt, Eduardo, and Coco to either stay upstairs or outside. After a series of ridiculous deciding, they choose to stay upstairs, but after being there for a while, they decide to go outside. Things are going well until Mac comes with video games and they realize they are stuck outside. the situation becomes chaotic as they try to get inside, and ruin things for Mr. Herriman and Frankie.
The series finale. When Herriman tells Bloo that Mac is moving, Bloo decides to give him the best day ever, though things do not go as he plans. All day, Mac does things with everyone but Bloo, making him angrier after every disappointment. However to everyone's surprise/relief (and Mr. Herriman realizes he forgot to mention this), it turns out Mac is moving to an apartment (the one next door) that was held by Louise's family, and with Cheese unable to follow her because her new home doesn't allow imaginary friends, he moves into Foster's. This was Craig McCracken's final project before he quit his job at Cartoon Network.
Mac and the other friends start a car wash to pay for a porcelain poodle that Bloo broke. To help, Bloo throws mud at every car that goes by to get more customers.
Frankie goes to a mechanic to find out about the bus, which had broken down, and everyone wants to come along, slowing her down.
Frankie tells Bloo that static electricity can be produced by rubbing socks together. After learning this, he zaps Frankie, then Wilt, then both Wilt & Frankie at the same time. Running through the halls, he zaps Madame Foster, Coco and Jackie Khones. He tries to zap Mr. Herriman, but nothing happens. Bloo "re-charges" by rubbing onto the rug, a towel, an imaginary friend, and two socks. After that, he gives Eduardo a big zap. But in the end, Bloo zaps himself while trying to get the door open for his package.
Bloo tries to make a good recording message for the Fosters Home phone, getting various others to help. Eventually, Bloo gets satisfied with one but Madame Foster plugs too many devices into the same outlet as the phone, fricassing the phone from the overload.
Mac and Bloo have a staring contest and Eduardo tries to talk to them only to think they're frozen solid, consequently getting Frankie to tell him about it. More of the house's residents watch in a bet, as Mac seems to start losing his grip, only to recover it. It is revealed that Bloo was hiding behind a cardboard cut-out of himself.
Bloo tricks Mac into making crank calls to Mr. Herriman. Their joke is simply blowing raspberries into the phone, redialing again and again. Each time Herriman tries to get back at them by doing the same thing, it isn't them redialing, it's Frankie asking about groceries in the mall. The last call Herriman gets wasn't from Mac and Bloo or Frankie. It was from Madame Foster.
Mr. Herriman tells Bloo to sort the trash for punishment because Bloo hosted a mud-wrestling tournament in the living room. Mac comes along and talks Bloo into pretending it is fun so that other people will want to do it. Soon, he has everybody doing it. Mac tries to tell him that it isn't fun after Bloo refuses to go do something else. He thinks everybody is gonna take the trash for themselves and tells them to get out. Then he realizes it isn't fun without the guys and walks away, until Mr. Herriman comes in and tells him to finish sorting the trash.
Bloo is determined to win a game of Hide and Seek, so he hides in the trash. Things go awry when a few friends start playing "Kick the Trashbag".
Bloo makes a commercial for Fosters and ends up in trouble when a bunch of people show up because he told them that the first people there in 10 minutes get money and the Fosters bus.
Bloo leaves the fridge open after getting himself a snack, which leads to Frankie telling Wilt to order pizza. Bloo tells him to order five hundred pizzas, at the price of $6532.12. Frankie can't pay that much, so Bloo, Wilt and Ed stall Quinn the delivery boy by sitting on him (because the pizza is free if it isn't there in 30 minutes).
Eduardo tries to draw a story but Bloo, Wilt and Coco keep interrupting him, drawing their own additions to the story. Frankie interrupts them, revealing that they had been drawing on a wall in the house.
Bloo tries getting a secret decoder ring from a cereal box. Mr. Herriman forbids him to get the toy without eating the cereal down to the ring. He then realizes that a secret decoder ring can decode his files on house residents and competes with Bloo in order to get the ring first.
Bloo finds a strange rock digging in the yard and it is declared to be a fossil by Phineus B. Vurm, the bookworm imaginary friend. Bloo treats it as a pet until Frankie reveals it's actually petrified feces.
Bloo tries to decipher a message from friends whose vocabulary has only one word each, like Coco. When he figures it out, he doesn't believe it until he realizes it is true.
Eduardo has a British penpal and Bloo is convinced that it's the Queen of England. He tries to make her his penpal instead by writing her a letter. Mac suggests to use Nancy, an English pen imaginary friend, but Bloo claims it'll make the letter "boring". Mac then suggests a care-package to make her really believe that Bloo cares. Bloo brings in a huge package, but it turns out the penpal was really Nancy. She claims the package is "boring" and she can only use it as a doorstop.
It's Bloo's birthday, and his cake is being guarded by Mr. Herriman. After being refused to have his cake, Bloo leaves and Frankie comes in and sees Mr. Herriman sleeping on the job. She makes it look like he ate the cake in his sleep and leaves. Mr. Herriman soon wakes up and notices this and thinks he indeed ate the cake, at which point Frankie is yelling for Bloo to come into the kitchen, as they both enter, Frankie sees the cake is gone and scolds Bloo for it and threatens to kick him out. Feeling guilty, Mr. Herriman confesses that he ate the cake, on which both Frankie and Bloo begin to laugh, saying they pulled a prank on him and that the cake is just fine. When Frankie opens the refrigerator to show that the cake is fine, it actually is gone, having been taken by Madame Foster.
Jackie Khones questions Bloo about Mac's backpack and Bloo becomes obsessed with finding out what's in it.
Bloo ruins Mac's hair with gum the day before School Picture Day. Bloo tries to make it up to him but only makes matters worse.
Blooregard plans to play the ultimate trick on Halloween after tying down Mac onto a bed preventing another sugar rush, but when things go awry, most of the main characters of the residence turn into zombies in 3D!
The plot of the special follows Frankie, who becomes trapped in a huge, mysterious world where she is treated like royalty but forced not to leave. Bloo, Mac, Coco, Eduardo, and Wilt journey through the world to rescue her, facing perils and challenges along the way.
