- Directors: Peter Segal
- Producers: James D Brubaker, Brian Grazer, Karen Kehela, Jerry Lewis, Eddie Murphy, Tom Shadyac
- Writers: Jerry Lewis, Steve Oedekerk, Barry W Blaustein, David Sheffield, Paul Weitz, Chris Weitz
- Genres: Comedy, Fantasy
- Actors: Eddie Murphy, Janet Jackson, Larry Miller, John Ales, Richard Gant, Anna Maria Horsford
As the film opens, Sherman is working on a new miracle formula â€“ this time, the fountain of youth. He is also preparing to marry a fellow scientist, Denise Gaines (Janet Jackson). Unfortunately, he has started suffering from personality lapses that are threatening to alienate his bride-to-be: against his will, he acts like the obnoxious, hypersexed Buddy Love of the first film. After a particularly unpleasant incident, Sherman goes to his lab to analyze his DNA and locates Buddy Love’s DNA in an abnormal gene. He decides to use Denise’s genetic research methods to isolate the gene and permanently extract Buddy Love’s DNA from his own. His assistant, Jason, tries to stop him, warning him that he might damage his health or even lose his intelligence. Sherman disregards the warning and, alone in his lab late at night, extracts Buddy’s DNA.
The orphaned DNA, a glowing blob of jelly, combines with a hair from a basset hound and grows instantaneously into an adult man, Buddy Loveâ€”now a fully autonomous being. Thanks to his doggy heritage, however, this Buddy Love has a tendency to chase cats and cars. Sherman, meanwhile, has inflicted so much genetic damage on himself by removing Buddy that his brain cells begin dying at an exponential rate.
Denise and Cletus arrive, and see Sherman and Richmond. Sherman, before his brain becomes seriously damaged, sadly tells Denise, whom he no longer recognizes, that he no smart, never, no more. Denise starts crying, and one of her tears lands on the dried blob, causing it to trickle into the fountain. As his companions begin to usher him away, Denise promising to take care of him, Sherman turns and mumbles something about “pretty water”. They see the fountain’s water glowing a bright neon blue. Denise realizes that Buddy’s DNA is still alive in the water. She and Cletus force Sherman to drink the water before Buddy evaporated, and he rapidly regains his mental faculties. In the last scene, Sherman and Denise get married. As in the first film, bloopers accompany the closing credits.