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.
Mac realizes that he accidentally created a new imaginary friend named Cheese. Cheese is allowed to stay at Foster's like Bloo, but Bloo has trouble dealing with his new brother Cheese.
Wilt is getting tense at Creator Day when Mac keeps mentioning the word "creator" to him. Wilt suddenly leaves in the middle of the night and the Foster's friends look for him.
Mac and Bloo both develop a crush on Frankie, and try to stop her from having any contact with any guy. Eventually, they follow her on a date while in disguise.
After Frankie leaves the keys in the bus, Bloo takes Mac on a joyride and gets lost. Wilt promises to keep it a secret, but has trouble not telling anyone.
Everyone begins preparing for the annual house photo, and Mac and Bloo try to solve the mystery of a strange photo taken years ago. Meanwhile, Coco tries to lose weight, Eduardo gets a makeover from Duchess, and Wilt tries to fit in the photo.
Cheese playing a game in his head. It begins with Cheese saying he likes games and sticking a video game cartridge into his mouth. He then goes into his imagination, He then says "'nother game." and sticks the game back into his mouth.