- Directors: Steve Anderson
- Producers: Dorothy McKim, John Lasseter
- Writers: William Joyce, Screenplay, Jon A Bernstein, Michelle Spritz, Nathan Greno
- Genres: Animation, Adventure, Comedy, Family, Sci-Fi
- Actors: Jordan Fry, Harland Williams, Tom Kenny, Steve Anderson, Angela Bassett, Laurie Metcalf, Adam West, Tom Selleck, Nicole Sullivan
The film begins showing a young woman leaving her baby boy on the steps of an orphanage. Twelve years later, this boy, called Lewis (Daniel Hansen and Jordan Fry), is an aspiring inventor. He has yet to be adopted and fears that he never will be. Convinced that his birth mother will want him, he attempts to invent a memory-scanning machine that will allow him to remember his mother in the hopes that he can find her. His roommate, Mike ” Goob” Yagoobian (Matthew Josten), becomes his assistant during long hours of building, which causes Goob’s Little League baseball team’s performance to suffer.
At Lewis’ school science fair, Lewis is approached by a thirteen-year-old boy named Wilbur Robinson (Wesley Singerman), who claims to be a “time cop” from the future and that a man wearing a bowler hat has stolen a time machine that Wilbur wishes to recapture. The sinister ‘Bowler Hat Guy’ (Stephen Anderson), sends Doris (Ethan Sandler), his robotic bowler hat with mechanical arms, to sabotage Lewis’ memory-scanner. As Lewis begins demonstrating the use of his machine, it explodes, throwing the science fair into chaos. Lewis runs out, and the Bowler Hat Guy steals his unattended memory scanner.
Cornelius (Tom Selleck) appears back from his business trip and meets his younger self. Wilbur fulfills his promise to Lewis by visiting the moment at which his mother abandoned him. Lewis nearly interrupts her from leaving the infant “him”, but stops, choosing his Robinson future over a childhood with his mother. Finally, Lewis returns to his own time and prevents Goob from becoming the Bowler Hat Guy by waking him up in time to catch the ball that wins him the game. Lewis then returns to the science fair and demonstrates his memory scanner on the science fair judge, Dr. Krunkelhorn (Laurie Metcalf), revealing that she is Wilbur’s grandmother, Lucille. Lewis also meets a young Franny, and flirts with her briefly. Bud and Lucille adopt Lewis, who adopts the name Cornelius and sets to work building Carl in an observatory bought by Bud and Lucile which one day becomes the Robinson house. Just before Lewis/Cornelius drives off with Bud and Lucille, he turns around and waves at Goob, who is also leaving the orphanage with his own new family.