Writer/director Atkins (who doubles as a rock drummer) is the son and brother of three dentists, which would be unremarkable but for the fact the Columbia University film-school grad has made the hero of his first feature a dentist. Frank Sangster (Martin) is a settled, vaguely smug guy with a prosperous suburban practice, a sleek house and an impeccable professional air. He's engaged to his perky, hyperefficient hygienist, Jean Noble (Laura Dern), and hasn't a care in the world.
Enter the obligatory femme fatale, wearing a blood-red blouse and a look of larceny. The moment Susan Ivey (Helena Bonham Carter) slithers into his office, Dr. Frank is a goner, although he doesn't want to admit it, even to himself. Catlike and captivating, Susan sets loose all kinds of half-formed fantasies in him, and even after she scams him for a Demerol prescription and cleans out the drug fridge, he can't get the hook out. Thus is another seemingly happy but deeply repressed citizen of Middle America drawn down into the dank netherworld of sin and violence, into back alleys and cheap one-night motel rooms -- with a couple of laughs, of course. Those who remember Martin as the sadistic dentist in the 1986 remake of Little Shop of Horrors will see a different but familiar bit of business in Novocaine -- an innocent man (innocent of some things, anyway) who suddenly finds himself on the run from the cops and the bad guys. Clearly Atkins has studied his Hitchcock, as well as Double Indemnity.
"One small lie," Frank tells us, repeating the lament voiced by seduction victims in six decades' worth of Hollywood thrillers, "and everything unravels from there." Before he knows it, mild-mannered, happy-go-lucky Dr. Sangster is stabbing a guy through the hand with a pair of scissors and searching his house for bloody intruders, armed with a huge steel sculpture in the shape of a molar.
Novocaine's strengths and chief amusements lie not in Martin or a predictably twisted plot but in an array of vivid supporting characters. The elfin, delicate Bonham Carter, a Londoner who has spent much of her movie career in whalebone corsets and chiffon (or ape makeup), speaking high-tea English for Messrs. Merchant and Ivory, gets yet another go, after Fight Club, at playing ultracontemporary and streetwise American. Her Susan is an accomplished con artist, a desperate junkie and a few other things, and by the time the movie's done she's completely seduced us, too. It's quite wonderful, the way she messes with dumb Frank Sangster's head: He's got no chance, and neither do we. Dern has her moments, too, as the karate-kicking, control-crazed dental hygienist. If we imagine her back story, Jean has to be a former sorority morals officer who's always had things her own way and is mortified if a wisp of blond hair goes awry. The contrast to Susan's hip slovenliness is perfection.
Further down the cast list, more gems. As it happens, both Susan and the good doctor have wacko brothers, and they are a ball to watch as long as the story keeps them around. The dentist's younger sibling is a greasy loser named Harlan Sangster (Elias Koteas), who is as thoroughly tainted as bro Frank is upstanding, and Susan's older sibling, Duane (Scott Caan), is a case-hardened psychopath with big eyes for Sis. Add a touch of incest to a noir cocktail that already includes murder, drugs, lust and blackmail, and you can see what kind of a horrible mess Frank has gotten himself into.
Way out on the edge of Novocaine we also find Kevin Bacon, in a surreal cameo as Lance Phelps, a vain Hollywood actor who's researching his upcoming role as a police detective by hanging out with the real thing. With Lance, director Atkins hits his comic stride: Unwittingly, the actor with the big ego comes closer than his new cop buddies to unraveling Novocaine's mess of missing drugs and scattered corpses. He also provides an escape route.
Unfortunately, Atkins has trouble keeping the tension high and the jokes rolling. Halfway through, he begins tripping over the noir genre's dark rules, and in the end he veers off into a haze of romantic redemption that Billy Wilder and Nicholas Ray would have scoffed at. This isn't to say movie genres can't evolve, or that an able moviemaker can't scramble them to useful and entertaining effect. But any time you propose to get down and dirty in double-crosses and betrayals, it doesn't do to let in too much sunshine, especially if you're the new kid on the block at midnight.