 After Madame Foster rescues an imaginary friend, she is treated as a hero by everyone. Bloo also wants to be a hero so he founds his own home for imaginary friends. Mac tries to make Bloo stop since his home is nothing but a cardboard box and the only "imaginary friends" are two puppets that Bloo calls  Purple  and  Sharkhead . Bloo mistakes a cat for an imaginary friend and makes a family adopt it. Soon Bloo remembers the great times he had with the cat and goes to the family s house to get it back.