KISS AND TELL

David Caruso is cold. He adjusts the heat in his L.A. home. ''I'm sensitive,'' he explains self-mockingly. ''I'd even go so far as to say I'm fragile.'' *That's not the first word that springs to mind to describe the man who won instant infamy by leaving NYPD Blue last fall to pursue a career in movies. But a few weeks before the April 21 release of his first name-above-the-title film, Kiss of Death, Caruso is in image rehab. He didn't talk much to the press during the furor surrounding his NYPD departure, when tales of his difficult behavior filtered out. (His tantrums were reportedly captured by NYPD cameras, and a New York Post writer said his ego was large enough to ''suck all the oxygen out of the Northern hemisphere.'') But now he's learning how to loosen up. *''I'm doing the press junket for Kiss of Death and people are like, 'Holy Mackerel, I think I like you!' '' Caruso says. ''They're like, 'Man, we were all sitting out there prepared for this horrible thing, and you're kinda funny and likable.' '' Caruso smiles, which is a strange sight to witness. His NYPD character, Det. John Kelly, was no joker, and Caruso has come across as guarded with the press. (Syndicated columnist Liz Smith called him ''one of the most unforthcoming interviews'' of her career.) Chilling out in the ''Gaudi-esque'' stone house he rents in Beverly Glen, Calif., he's dressed casually in an all- black ensemble-T-shirt, jeans, and socks. But he still occasionally speaks in a kind of code, keeping a distance from touchy topics. For the first two hours of the interview, he never utters the words NYPD Blue; it's always ''the television show'' or ''the show.'' Only later does he speak its name. And when asked about kids, he refers to having ''a guy through a previous relationship''-actually ex-girlfriend Paris Papiro's 6-year-old nephew, Houston, for whom Caruso is a father figure. Caruso also shares custody of his 10-year-old daughter, Greta, with his second wife, actress Rachel Ticotin (Total Recall). Caruso's life got more complicated last October, when Papiro, an ex- masseuse who was Caruso's live-in companion from 1990 to '94, hit him with a palimony suit. ''It was an unfortunate end to a basically successful relationship,'' says Caruso. ''I think we're gonna be able to resolve it.'' The 39-year-old native New Yorker now lives with new fiancee Margaret Buckley, a former flight attendant in her late 20's. ''We're trying to make a go of a traditional setting,'' he says. ''Which is what we both want.'' Agreements weren't always so easily reached between Caruso and director Barbet Schroeder (Single White Female) on the set of Kiss of Death, in which the actor plays Jimmy Kilmartin, an ex-con trying to bring down a mobbed-up strip-club owner (Nicolas Cage). Though Schroeder praises Caruso as a ''totally natural'' actor, the two sometimes clashed over Richard Price's screenplay. ''I wanted him to say the dialogue exactly, but he didn't always see it that way,'' says Schroeder. ''Maybe coming from TV he wasn't used to respecting dialogue.'' Caruso counters: ''I believe the script is the blueprint for the movie, and the first take is the second draft of the script.'' Kiss producer Susan Hoffman takes a big-picture view. ''The dialogue drove David a little crazy,'' she says. ''He's a big perfectionist, and he definitely causes himself some trouble. But he's worth the trouble he causes.'' Caruso isn't the only famous troublemaker on the set of his next movie, Jade; the writer, Joe Eszterhas (Basic Instinct), and director, William Friedkin (The French Connection), are also magnets for controversy. The plot is an Eszterhas special: Caruso plays a San Francisco DA who reignites an affair with a married psychiatrist (The Last Seduction's Linda Fiorentino) who might be a psychopathic killer. But on his day off from filming Jade in L.A., Caruso seems at ease; he eats a turkey sandwich fixed by Buckley, sits in an armchair listening to blues on the radio, and stretches out on a chaise longue on the back deck, all the while talking about his turbulent life. Meet the kinder, gentler David Caruso: