Plot
In North Philadelphia, Doris Robertson is a depressed teenager grieving the death of her grandfather and resisting her foster sister Lauri's efforts to engage socially. Upon learning that her parents will be away for a two day business trip to the Poconos, Doris' tear hits her television remote, as Fat Albert and the Cosby Kids is on. When the tear opens up a portal to the cartoon world, Fat Albert jumps out of the television upon seeing Doris (except real-life), knowing she has a problem.
Rudy, Dumb Donald, Mushmouth, Bucky, and Old Weird Harold jump out, too; Bill tells Russell to stay put and cover for them. Doris insists she is fine, but the gang knows otherwise. When the show ends, they have to wait until tomorrow's show to come back. They follow Doris to school and are amazed by the new technology.
Albert becomes infatuated with Lauri. Reggie, an annoying schoolmate with an obsessive crush on Lauri, challenges Albert to a track race that Albert wins. In another attempt to help Doris, the gang persuades cheerleaders to invite them all to an outdoor party. With some reluctance, Doris agrees to attend. While at the party, Lauri dances with Albert. Reggie desperately attempts to make her jealous by dancing with Doris. When Lauri does not notice him, he tries to forcibly kiss Doris. Doris yells at him and runs off. Albert warns the boy to stay away from Doris.
The next day, Doris goes to school but asks the gang to go to the park instead of following her. Harold, normally clumsy, joins in a basketball game and is able to play perfectly. Mushmouth, who cannot talk normally, is taught how to speak by a little girl. Donald goes to the library, where he can read and remove his pink face covering hat.
When Doris takes them home, three of the gang members – Bucky, Harold, and Donald – jump into the television. Breaking News interrupts the show before the other four can enter. Albert, Doris and Bill have an argument in private about going back. The gang takes Doris and Lauri to a fair on a junk made car. Doris says she would date Rudy if he was a real person when he asks.
Searching for guidance, Fat Albert meets his creator, Bill Cosby, and tells him of the dilemma. Though frightened and skeptical at first, Cosby proceeds to explain to him that his character is based on Doris' grandfather, Albert Robertson, which explains Doris' confusion over why Fat Albert seems so familiar. Mr. Cosby warns Fat Albert he has to return to the cartoon world, or he will turn into celluloid dust.
Devastated, Albert tells Lauri he must leave, but she thinks he is being insensitive. The next day, Mushmouth, Rudy, and Bill jump back into the television. Albert goes to a track meet where Doris and Lauri are competing and encourages Doris to a victory. Reggie, who witnessed that the gang is from the television, attempts to threaten Albert, but he pushes him aside. Albert rushes to the girls' house on a borrowed skateboard. He says goodbye to Doris and Lauri and jumps back into the television, and manages to take back the focus of the show from a gang of bullies that threatened to do so earlier in the film, as seen by Russell.
Sometime later, Cosby, his brother, and their friends who helped inspire the cartoon characters from the show, stand in front of their old friend Albert Robertson's grave. As the camera pans on each of the men, images of their counterparts are seen. Doris watches them from afar as the old men race away, showing that they are still kids at heart, the same kids from the television show that they helped Bill Cosby inspire. Before the ending credits start, Fat Albert encourages the audience to finish watching the credits and help each other.
