The day of Madame Foster’s birthday comes around and Frankie has forgotten to buy streamers, so Mr. Herriman orders her to go get some. Mac, Bloo, Eduardo, Wilt, and Coco tag along, but wander off while in the mall and get into various scrapes, slowing Frankie down.

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 lemonade in the middle of winter fails. When they finally get enough money to buy a new roof, Bloo sets himself up as the town’s cookie mogul.

Bloo wakes up to find the house completely deserted. With no Herriman or Frankie there to enforce the house rules, Mac and Bloo set out to cram as much fun and mischief into one day as they possibly can.

Mac seeks the aid of Jackie Khones to find out who stole his library card and used it to check out a now overdue book.

Mac and Bloo ask Mr. Herriman to go camping. He refuses to let them go, but Madame Foster thinks it is a great idea. After they arrive, Bloo has eaten all the food. Mr. Herriman then sets off into the woods in search for more food, and then meets wild bunnies. Meanwhile, back at camp, […]

When various imaginary Santa Clauses are brought to Foster’s, Mac begins to lose his faith in Santa’s existence, so it is up to Bloo and the others to help restore Mac’s faith in the old St. Nick. Bloo sends Wilt on a sleigh ride around the world and tries to get Eduardo to slide down […]

During the production of the home’s newspaper, Uncle Pockets, the most frequently adopted imaginary friend to come to Foster’s, returns yet again. Uncle Pockets’ charm drives all the other friends’ attentions to him, making Bloo jealous. Bloo then decides to try to expose Uncle Pockets as a fraud through the home’s newspaper.

In this double-length special, it is time for the Five Year Creator Reunion Picnic, where imaginary friends’ creators come to Foster’s to see their former friends. One friend’s creator, however, is missing: Wilt’s. Wilt, believing that his creator is still mad at him for a past let-down, sets off on a cross-country journey to set […]

Bloo becomes tired of always losing to Mac at everything, so one day at the Prize Hive, he challenges Mac to a thirty-mile race back to Foster’s.

Mac drafts the gang onto Madame Foster’s bowling team to help her beat her arch-rival Jerkins, but when Mac gets booted off his own team, he must learn the ways of the ball from an imaginary bowling guru.

Foster’s is being put on the local news and Frankie wants everything perfect, but the only thing standing in her way is Cheese who keeps showing up at Foster’s uninvited. In an attempt to keep him out, Mr. Herriman installs a security system. Unfortunately, due to misreading the instructions, everyone gets locked out of the […]

Mac takes Bloo to school for show-and-tell, and his classmates love Bloo so much that they imagine their own Bloo knock-offs. Hundreds of Bloos come to Foster’s the next day and Bloo dubs them his minions, but when Mac shows up to take Bloo to see the Ice Charades, he cannot figure out which Bloo […]

Bloo is tired of Madam Foster getting all the glory for rescuing abandoned friends, so he sets up his own foster home – Bloo’s Foster’s Home for Imagainary Friends – in a cardboard box on the sidewalk.

All Wilt wants to do is watch a basketball game on TV, but the house’s ridiculous requests and Wilt’s inability to refuse them keep him from seeing the big game.

When Mac takes his classmates on a field trip to Foster’s, everybody loves Coco and Bloo wants all of the attention. After Coco lays eggs with imaginary friend trading cards, all of the friends start trading and collecting the cards. Bloo becomes obsessed, and tries to be the first to collect them all.

Bloo visits a retirement home and disguises himself as a senior, getting to live there and being pampered all day long. When Mac finds out about it, Madame Foster teams up with him in order to get Bloo out of there.