movie trailer (apple.com - quicktime)
NOTE: This spoiler was sent in from Holland by M.O.Slim ...
An unpopular girl named Doris is not invited to a certain party thrown by a bunch of cheerleaders. Her gorgeous sister is invited. Doris goes home to watch the Fat Albert and the Cosby Kids Show, which is a cartoon. In the cartoon there is a character that looks like Doris and has her own problems. This reminds Doris of the unfortunate situation she's in, having no friends, and she starts crying and suddenly a teardrop enters the Fat Albert Show. Since Fat Albert is a problem solver, he starts looking from where this tear came. He sees a blur in which is a girls face (Doris'). Fat Albert then jumps into the blur and enters the real world, becoming Kenan (from the Kenan & Kel show). He's a fat guy, so he gets stuck in the television set, while Doris is terrified with what's going on.
After Fat Albert and his gang enter the real world, F.A. asks Doris whether she has a problem. She says she doesn't, but F.A. knows better. F.A. and the rest accompany Doris to her school. They don't fit in with their colorful clothes and their strange habits and weird appearances. F.A. stands up and tells the class they should be friends with Doris. This only makes the humiliation bigger for Doris.
Outside on the tracks, which is a favorite hobby of Doris, F.A. meets Doris' sister Lauri and he immediately falls in love with her. This annoys Reggie, who's after her heart too. Reggie makes fun of F.A. and wants to race him. F.A. wins the race and the Lauri's heart.
Meanwhile the Cosby kids' colors are fading, for they don't belong in this world, rather in a cartoon.
At the cheerleaders-party Reggie makes fun of F.A. again and invites him to the stage to sing something. F.A. appears to be a great rapper/ entertainer, which again is a bad thing for Reggie. While F.A. and Lauri dance, Reggie dances with Doris, trying to kiss her. Doris doesn't like this and she runs away.
In the real world all the cartoons lose their specific habits: Mushmouth learns to speak normally, the long dude learns to play basketball well and Dumb Donald appears to be a smart dude.
One night F.A. and the gang decide to have fun with the sisters and take them to a carnival. F.A. is scared of the roller-coaster. Meanwhile in the cartoon, one of the Cosby kids is in trouble and shouts for help to F.A. This is being reported to F.A. by a kid who's on the carnival too. F.A. realizes he doesn't belong in this world and decides to break up with Lauri. She doesn't understand.
The next day, there is a race to be won by Doris and Lauri. F.A. cheers for them, but doesn't have a lot of power left to survive in this world. The sisters win the race and urge back to help F.A. get back into his cartoon. When they arrive F.A. tells Doris that her problem isn't a problem. The love for her dead granddad will keep the fire in her soul burning. The sisters manage to get F.A. back into his own world and F.A. solves the problems that were going on while he was gone.
In the end we see Doris visiting her grandfathers grave and we see Bill Cosby too. With him we see all the characters from the F.A. and the Cosby Kids Show, grey and old, standing before Doris' grandfathers grave. On his stone we see the name Fat Albert.