G-Force is introduced and faces a challenge against one of Spectra's most mightiest machines, the Space Terrapin. To control the Universe, Spectra will stop at nothing to steal Earth's most valuable mineral: Vitalumis. Mark, Jason, Princess, Keyop, and Tiny (with help from 7-Zark-7 at Center Neptune) power The Phoenix to victory over Zoltar and Spectra.
Upon their splashdown on Earth, two astronauts are kidnapped by a Manta Ray submarine for discovering the location of Spectra bases on Mars. G-Force is called upon to resuce the astronauts and retrieve the valuable information they obtained. Mark infiltrates Spectra's base, and is later joined by Keyop to return the astronauts to The Phoenix. The Spectra Commander escapes in the head of the Space Terrapin, only to be destroyed by the Fiery Phoenix.
7-Zark-7 discovers a new planet, which is called Zarkadia in his honor. G-Force learns that several mysterious plane crashes have been occurring on the planet, so Mark travels undercover to investigate. There, he meets Dr. Sweet, who has developed a compound that can render Spectra's latest weapon useless. Sweet hid his creation in his nephew's toy, whose father was a pilot of a plane lost and spends all his days at the airport waiting for his father to return. When it seems like the pilot does indeed return, Sweet is first very happy his brother was back, but then realizes it wasn't him and finds the imposter trying to break into his personal safe. It turns out to be Zoltar, looking for the compound. In the meantime, Mark discovers Spectra is using a giant mummy to bring down the planes, and the rest of G-Force joins him, using Sweet's compound to destroy the mummy. With the compound secure, Spectra will never be able to use their weapon again.
Out of all the pilots in the Federation, Mark has been selected to test the Space Patol Scout (XF-97) , to be used in Galactic Security. In the midst of the flight he is attacked and downed by Captian Doom from planet Ergos, who is a space pirate. Mark ejects to safety while Doom attacks the airshow uses a laser whip. The Phoenix is forced to land after its rudder is destroyed. From the rudder of the Phoenix, a sample of the metal from the whip is found, but Center Neptune scientists donÕt know what it is. The team heads to Ergos to search for the source of the metal before other weapons constructed with it can be used by the Space Pirate.
Commander Typhon from planet Scorpius is an exile who wants Zoltar's help in defeating his rival opponants on his planet In exchange Typhon gives Zoltar a new weapon, the Scorpion, that creates meteor showers. In hopes of averting the destruction of Capital City, G-Force heads for the Jupiter moon of Callisto. The Scorpion then heads for Earth, before the team can destroy it. Finding a submarine at the bottom of the ocean that is controlling the Scorpion and asteroid showers. Typhon escapes the submarine, trapping G-Force inside.
After the city is blacked out, G-Force heads out to find out why. They find a swarm of ants attcking the Solar Fusion Plant. After flooding the ants away from the complex, they find the remants of one, finding that they are tiny robots. From the construction, Center Neptune scientists ascertain that the threat this time is not Spectra, but Tromulous. The team heads out to stop this lates threat. Once on Tromulous, they set down the robot ant and follow it to its home. They come to a giant ant hill, and before they can make a plan, the sand opens up under their feet.They find themselves captured by Commandeer Antof who has struck a bargain with Zoltar giving him Earth if he kills G-Force. Keyop sets chargesto the bubble that entraps the team, enabling them to get out. out of a giant cocoon a queen robot ant hatches.and heads for Earth.
Spectra sends a mechanical whale to Earth. The Mecha attacks Bay City and G-Force goes after it. The Team interrupts the Spectra ship as it attacks some whales and Keyop promptly adopts a baby whale that survived. G-Force must locate the Spectra base and stop Zoltar before he destroys all of Earth's whales!
Professor Doriarity is recruited by Spectra to make a robot horse army. The Great Spirit makes the Professor the new Ruler of Spectra in exchange for the army and G-Force goes to Spectra to stop him. They arrive to find that Spectra has turned on the Professor and they must now rescue the Professor and stop the robot horse army.
Spectra unleashes what looks like a giant bowling ball on Earth, and G-Force is helpless in stopping it. None of the Phoenix's missiles or defenses can stop the giant ball. While on a break to ponder the possibilities, Mark sees Keyop playing with a magnet and ball, given to him by Zark. Mark gets the idea to build a giant magnet to attract and destroy the giant ball. The plan is to use the Phoenix to lure the ball into the magnet. When that fails, Mark infiltrates the ball and takes control, sending it into the giant magnet, destroying both. The other G-Force members think Mark is killed in the explosion. However, as all are standing around the fire in tears, Mark flies down from the sky to join them without a scratch.
Jason enters a continental auto race with a fellow driver named Lucy. However, Lucy is not all she seems to be. Although used by Spectra to infiltrate G-Force via Jason, Lucy is not able to compete her mission because she has grown fond of Jason. This is quite a feat, especially after the revelation that she is a robot!
What at first appears to be an exceptionally high powered typhoon hits the world's largest water reserve center in cosmic city. For some unexplained reason, the weather control missiles which could have deflected the storm, were never launched. Chief Anderson tries to convince the leaders that the storm was no accident of nature, while G-Force investigates some unusual activity and a possible Zoltar connection.
G-Force is headed for their mountain retreat headquarters for a few days. Jason is driving Chief Anderson when they are attacked by a strange car and a woman wearing a mask. Only Jason's skill and a hidden capability of the car they are riding in save their lives. Zoltar's sister Mala is put in charge of sabotaging the Solar Express, the first monorail to circle the globe. Mala pretends to be with Public Relations as Marla Latras, in order to ride on board with Chief Anderson, who is accompanied by Mark. It soon becomes apparent Mala has more in mind than to destroy the Solar Express, but also plans on eliminating Chief Anderson himself!
Tiny's van breaks down and he is picked up by a Prison van on its way to Barracuda Island, a maximum securty prison. Spectra's gains control of the prison and Zoltar has promises freedom to the prisoners if they will join Spectra. The G-Force team must rescue Tiny and keep the prisoners from escaping.
A young, married couple stayed behind to help defend a base from an attack by Spectra. Both survived and were brought back to Earth as heroes. Zoltar wants to eliminate them (both are eyewitnesses to the Spectran attack) and both have parents that are highly placed in the government. He orders them kidnapped and brought to Spectra. It's up to G-Force to rescue the two from Zoltar.
Riga is attacked by Spectra and Chief Anderson is not sure how to defend against Spectra's new weapon, making the team wait. G-Force grows impatient and rushes off to Riga without any planning or orders. They are badly defeated and have to be rescued by Colonel Cronos. The Team is sent back to Earth, where it becomes apparent that Mark has lost his confidence. Cronos tests Mark's confidence by challenging his nerve while flying. Mark fails, but a little later, while talking with others, he comes up with a plan to defeat Zoltar's Mecha. G-Force flies back to Riga and engages the Spectran mecha in a fight.
Spectra attacks the Artificial Brain Center on Earth and steals a top-secret "Brain of Evil". The Team tracks down the stolen brain, only to be attacked by the Brain Mecha and then Spectra Pirates! G-Force returns with a piece of the Mecha to Center Neptune, and then attends the Annual Robot Show the next day, just in time to watch Spectra steal the new "Fembot" to use as a body for the Brain of Evil. Mark sneaks into the Spectra base while the rest of the team goes after the Brain Mecha.
This episode takes place on planet Exor. One of their island cities is surrounded by an impenetrable wall of radiation created by a Spectra bombing attack. Chief Anderson believes the city is a Spectra base and sends G-Force to check it out. The team goes into the city, but they are only able to withstand the radiation for one hour. They are attacked by a Spectra Mecha once they are inside the city. Can G-Force escape the Mecha and solve Spectra's latest plot before their time runs out?
Jason rescues a girl in a cab who is attacked by strange robotic manniquins. Upset that Mark doesn't trust the girl, Jason goes to talk with her, only to find Mark may be right. As a series of attacks terrorize the city, G-Force split up and head into the city to try and track down the attackers and stop them. Matters are made worse as one by one, the members of G-Force start disappearing...
Spectra is using Bigfoot to keep people from getting too close to their latest base in Tibet. They are working on the "Inter-Frequency Disruptor", which affects ships guidance systems, causing them to crash. Keyop takes off for Tibet on his own and is captured by Spectra. He must lead G-Force to the Spectra base and escape before it's destroyed by G-Force. Zoltar is unmasked in this episode!
In Spectra's latest attack, they send locusts to devour Earth's food supplies. Professor Chambers contacts G-Force and they send Keyop back with him to South America. They are attacked by the locusts and forced to crash land in the Amazon. G-Force must rescue them and stop the Giant Locust from destroying the Earth.
Spectra targets one of the richest countries on Earth, the small country of Beldania. G-Force is dispacted out to talk and protect the monarch, but right from the start things seem wrong. Sneaking into the palace at night, to avoid detection, they find the palace bobby-trapped and full of dangers. When they finally find the monarch, they find an imposter in his place.
Spectra steals the Conway tapes. Mark and Princess are trapped on a Spectran spy ship and taken to planet Spectra. They recover the Tapes and try to escape, but are captured by Spectra. Jason, who has followed them without orders, rescues them and they must battle their way through the Spectran defenses to escape.
A TV movie called "Battle of the Planets: The Movie" was made by Gallerie International Films and Sandy Frank Film Syndication. David Bret Egen was the voice of 7-Zark-7. The movie was combined from several episodes to form a new story line which contained violence as well as deaths. It was considered for an uncut remake of Battle of The Planets, but was scrapped when plans changed. Sandy Frank began focusing efforts on arranging an uncut dub of Gatchaman instead.