Osmosis Jones

The City of Frank is a bustling metropolis with ghettos, criminals, a hard-working police department and a fat-cat political system. It is just like any other major city, except that it is located within Bill Murray’s body.

In “Osmosis Jones,” Bill Murray plays Frank, a 40-year-old man who is blithely ignorant of health or dietary concerns, and who is unaware that within himself — indeed, within every person — exists a complicated, multi-faceted world of cells, muscles and tissue, all trying to eke out their own existence while contributing to the betterment of the whole.

Directed by gross-out kings Peter and Bobby Farrelly (“There’s Something About Mary,” “Dumb and Dumber”), “Osmosis Jones” takes place both in Frank’s world and inside his body, the latter locale provided by amusing and colorful animation.

Chris Rock is the voice of Osmosis Jones, a loose-cannon white blood cell who works for the Frank Police Department. A couple years ago, he made a hasty decision to expel some bad oysters from Frank’s stomach, causing Frank to vomit on his daughter’s schoolteacher and resulting in much embarrassment for Frank as a whole.

As a result, Osmosis was busted down to more menial duties: patroling the mouth for tartar, looking for germs, that kind of thing. But when a seemingly unimportant sore throat turns out to have been caused by a deadly virus (voice of Laurence Fishburne), it’s up to Osmosis and his do-gooder cold capsule partner Drixenol (David Hyde Pierce) to save the day — indeed, to save all of Frank.

The idea of a man’s insides being a city is a wonderfully entertaining one, with opportunities for so many jokes. We’re told that the Love Handles district is “the fastest-growing community in Frank,” and the mayor (William Shatner) is thrilled to announce they’re about to begin construction on a third chin. The Mafia hangs out in the armpits, because that’s what most closely resembles a sauna. To find a good lawyer, head down to the hemorrhoids. In the brain, Frank’s “guilt” censor is a cell dressed in priest garb and holding a Bible. In the labyrinthine, unsettling Subconscious, we see dreams — projected on movie screens, of course — with titles like “He Didn’t Study for the Exam!” and “Girls from the Bus Stop.”

It’s such an amusing concept, in fact, that the movie should be funnier. While the animated parts are inventive and sly (there’s a truly wonderful “Titanic” reference, balancing out the now-obligatory and unfunny “Matrix” one), the live-action stuff squanders the considerable talents of Bill Murray and the lesser-but-still-noteworthy talents of Molly Shannon and Chris Elliott. Frank is Unhealthy, his daughter (Elena Franklin) is Concerned. They have no other attributes, making for a very thin, broad story frame.

Fortunately, the guts (pardon me) of the story — i.e., everything animated — outweigh the paltry live-action offerings. Parents may not want their kids revelling in such body-oriented humor, but at least the myriad sexual jokes that were possible have been omitted. For grown-ups, it’s not a classic — I suspect a second viewing would yield few laughs — it’s good while it lasts.

B (; PG, gross bodily humor.)