Osmosis Jones is a 2001 American live-action/animated action comedy film written by Marc Hyman. Combining live-action sequences directed by the Farrelly brothers and animation directed by Piet Kroon and Tom Sito, the film stars the voices of Chris Rock, Laurence Fishburne, David Hyde Pierce, Brandy Norwood, and William Shatner alongside Molly Shannon, Chris Elliott, and Bill Murray in live-action roles. It follows the title character, an anthropomorphic white blood cell, as he teams up with a cold pill to protect his unhealthy human host from a villainous virus.

The film premiered on August 7, 2001, and was released theatrically three days later. It received mixed reviews from critics, who praised the world building, the animation, story, and voice performances, but criticized the inconsistent tone of the live-action portions and overuse of gross-out humor. The film was also a commercial failure, grossing $14 million worldwide against a $70 million budget. Despite the poor financial response, the film was followed by the animated television series Ozzy & Drix, which aired on Kids' WB from 2002 to 2004.