There must be something in co-writer/director Harold Ramis’s childhood that would explain his addiction to unnecessary sequels. Or maybe it’s just the box-office receipts. First, there was Caddyshack II, then Ghostbusters II, and now, bringing back America’s second-favorite Mafia don in therapy, Analyze That.

The film begins with Robert De Niro’s Mafia boss, Paul Vitti, in jail and faking insanity (he won’t stop singing West Side Story tunes). He’s released early and, as only movie logic could dictate, into the care of his old shrink, Ben Sobol (Billy Crystal). The point here is not the material but the obvious enjoyment that Crystal, who’s largely the straight man, and De Niro take in playing off each other. It’s the same infectious joie de vivre that infuses and saves Adam Sandler films: the whole endeavor seems less about making a film than about hanging out with friends.

There’s also the corny humor that made Analyze This such a hit with everyone’s parents; the set-ups to old-fashioned gags have all the subtlety of a dead body getting thrown into a trunk. But Ramis, Crystal, and De Niro are pros, and you may be surprised how much you find yourself laughing. Lisa Kudrow returns as Crystal’s wife, and Cathy Moriarty-Gentile, who played De Niro’s wife in Raging Bull, appears as a Mafia queen. (95 minutes)