Madame Foster, the sweet old lady, with a big, proper bunny (named Mr.Herriman) for her imaginary friend, opens her large, Victorian mansion to all imaginary friends in need of a home, after being abandoned by their creators. Thus marks the birth of Foster's Home for Imaginary Friends, the adoption center for imaginary friends, where they can live untill a kid comes along who, for one reason or another, cannot make one for himself.
One day, a clever, yet somewhat shy 8-year-old, named Mac, is told by his mother that he is too old for his imaginary friend, the protector, yet goofball, Blooregard Q. Kazoo (aka Bloo). She believes that, if the one big thing Mac has outgrown is out of the picture, there may be less fights caused by Mac's doofus bully of a 13-year-old brother, Terrence.
Seeing an ad for Foster's, on TV, Bloo is convinced that this may be the place for him. After a quick tour of the crazy place, and after meeting some fun friends--Wilt, the basketball loving friend that is always willing to help, Coco, the crazy bird who lays plastic eggs with prizes (and only says the word "Coco"), and Eduardo, the scary-looking monster-like friend, who is, actually, scared of everything - Mac is convinced, too...
That is, until what they thought was some sort of boardinghouse-like place turned out to be a foster home. Bloo was shocked when he found out. "Adoption is not an option!" he says, attempting to leave. But, Mac promises to find a way to make them let him stay there, without letting him be adopted by anyone. So far, all he can do is just be there whenever he can, since, when the creater of an imaginary friend is present, he/she cannot be adopted. However, if he is not there, and Bloo is selected for adoption. Then a little girl came and wanted to adopt Bloo. Mac was not present at the time so Wilt, Coco, and Eduardo began the chase to protect Bloo and after Frankie (Madame's granddaughter) convinced the girl's parents to adopt a snooty imaginary friend, Duchess the girl imideatly said no.Then Mac arrived Duchess was not adopted and all was perfect. Until...
Feeling angered, Duchess teams up with Terrence to get rid of Bloo once and for all. Terrence locks Mac in his room Duchess distracts Wilt, Frankie, and the others and Terrence adopts Bloo and they were off to the junkyard and when Mac escaped he went straight to Foster's and there they discovered about the evil plan. Mac, Wilt, Coco, and Eduardo went to the junkyard to rescue Bloo and there Duchess unleashed a monster. The monster attacked them all until Mac and the others were able to trick the monster into eating Duchess and Terrence ant the monster spit them out Frankie and Herriman arrived they put Terrence in a unicorn stable wich the unicorns attacked him and made Duchess stay at the home because she doesent like it there. Mac was able to srike a deal with Madame Foster's: if Mac is able to visit every day at the home Bloo will not be able to get adopted.





