Nutty Professor II: The Klumps

In Nutty Professor II: The Klumps, Sherman the courtly nerd, his hippo physique draped in chemistry professor tweed, discovers that he’s still got a few traces of Buddy Love left inside him. He devises an experiment to cast the vicious swinger alter ego out of his hulking body, and Buddy, free at last, begins to saunter around town, and also to chase the occasional tennis ball and poke his head out of car windows, since he has accidentally been cross-fertilized with a dog’s DNA (don’t even ask).

It’s easy to understand why Sherman would want this guy purged from his system. As Buddy, Eddie Murphy, appearing in the guise of his rascally ”old” self, tries to inject the movie with a speedball of malevolent joy, but he’s antsy and high strung, flashing an autodestruct rictus smile that might look ironic if it weren’t so deadly forced. In last summer’s ”Bowfinger,” Murphy overdid the scaredy-cat paranoia, and he’s hardly more relaxed now. When did this fearless comic smoothie turn into such a tightly wired, pop-eyed hysteric? Buddy, of course, is meant to be Sherman’s id, and the movie’s as well, but here, even more glaringly than in his triumphant 1996 version of ”The Nutty Professor,” Murphy as Murphy is the least funny thing on screen.

It’s Granny Klump who’s the real id of ”Nutty Professor II.” Each time Murphy, as Granny, shows up in powdery white hair, with an icky grin of gums and sparse teeth, a body coiled over in geriatric resentment, and a voice so basso and venomous it could practically be channeling Satan, he gives his lines a whiplash sting, and the movie carries a charge. This little old lady isn?t just mean — she’s lusty and proud of it. Granny, far more than Buddy, lets Murphy tap the jubilant demons he’s still got inside him.

If ”The Klumps” feels like a major comedown from ”The Nutty Professor,” that’s partly because the novelty is gone, but also because the picture is messy and scattershot, with a plot that’s little more than a dirty version of ”Flubber.” This time, the center doesn’t quite hold — that center, of course, being the blimpy, brainiac Sherman, with his nervous polite chuckle, his ”tank on the dance floor” ’70s soul moves. Though Murphy’s performance is every bit as understated as it was the first time, Sherman is no longer a fresh creation, a slyly touching confession of Murphy’s own insecurity. Since the character has already conquered his self-hatred and won the affections of the pretty professor Denise Gaines (Janet Jackson, looking as airbrushed as she does on a CD), he seems quaint and predictable now.

The director, Peter Segal, and his team of screenwriters come up with the gimmick of having Sherman, via the Buddy Love separation experiment, gradually lose his intelligence. There’s one lively scene: Sherman, at dinner with Denise’s parents, uses a corncob to launch into a scramblingly idiotic, and raunchy, explanation of his latest theorem. The movie, though, needed more of that sort of verbal china shop bashing. The Sherman as idiot idea is never exploited for its full madcap potential. Instead, it’s the film that grows dumber, though in a boisterously crude way that’s occasionally amusing. The giant hamster who gets friendly with Larry Miller’s dean may be the most roguish anthropomorphic rodent since ”Caddyshack.”

What’s left for Eddie Murphy? Snappy as he is playing the Klumps, I’d hate to see him reduced to a trash-talking humanoid doll. He could probably go on grinding out mediocre hits, but his most creative opportunity might be to get back to stand-up comedy and come clean, once again, with his audience about fame, gossip, growing older. He can’t hide inside a latex bodysuit forever.