Baba Pink is making a moonrock cake for Moon! Bustling around the kitchen, she gathers all the ingredients but soon realises they have run out of moonrock. Luckily, Baba Blue comes to the rescue, having seen a piece of moonrock on a cloud earlier that morning. He takes Bluehorsey and sets off to fetch it for Baba Pink. Baba Blue collects the moonrock in a basket, when a cheeky-looking grey cloud bobs over and lands in front of him. Baba Blue frowns and shoos it away. But this naughty cloud is not to be dissuaded from getting in Baba Blue's way. Jumping on Bluehorsey, Baba Blue chases the cloud as it zooms ahead of him. Bluehorsey is tiring from all the extra weight of the moonrock so Baba Blue pops the basket on a cloud so they can continue their chase. Finally rid of the cheeky cloud, Baba Blue and Bluehorsey return to pick up the basket of moonrock - but it is nowhere to be seen. Baba Pink is very sad to hear that the moonrock has been lost - but she soon brightens and suggests they should look for it together in the skytrain - two Cloudbabies is always better than one! The sky grows thicker with grey clouds. With a storm brewing, the Cloudbabies know they need to find the lost moonrock quickly.