Never mind pointing out that Jack Nicholson and Diane Keaton are not as zany as, say, Cary Grant and Katharine Hepburn in their heyday--or that they may be a bit too old for nude sexual frolics in front of the camera. Forget all that. The whole point of Something's Gotta Give is that you're never too old to fall crazy-in-love--and Jack and Diane are just the couple who can convince us the best may be yet to come.

Nicholson plays a 64-year-old New Yorker named Harry, a successful entrepreneur and a celebrated ladies' man, and Keaton is Erica, a successful and even more celebrated playwright in her mid-50s. Harry has a lot of women in his life, but he only dates the really young ones, like Marin (Amanda Peet), who happens to be Erica's daughter. Since her divorce (from a briefly seen character played by Paul Michael Glaser), Erica doesn't date at all.

Harry and Erica meet for the first time when Marin takes Harry out for a romantic tryst (their first, apparently) at her mom's posh beach house in the Hamptons. Are they ever surprised to find Erica there, having arrived unexpectedly along with her sister, Zoe (Frances McDormand), to spend a quiet weekend. Erica is shocked, of course, that her daughter is dating a man as old as her father, and she loathes Harry on sight. But still, everyone agrees to make the best of the weekend, and Harry gamely tries to be polite--even when Zoe, who teaches feminism at Columbia University, lets loose with some of her pithiest observations on men of Harry's ilk. (McDormand is swell, as usual, but don't blink or you'll miss her.) Things get worse for Harry when he retires to the bedroom with Marin: Before his Viagra can take effect, he keels over from a heart attack.

At the local hospital, a handsome young doctor (Keanu Reeves) reassures Harry his attack was a mild one, and he'll be just fine--after a week or two of recuperation. Since he's forbidden to travel during that time, Harry moves back into Erica's guestroom. Prior commitments call Marin and Zoe back to Manhattan, so the two antagonistic protagonists find themselves alone together, and the inevitable warming begins--leading to one hot night in the master bedroom. Both are overwhelmed by the experience--although for Erica it's love, and for Harry it's euphoria over his post-heart-attack, Viagra-free potency.

Because Keaton and Nicholson are who they are and what they are (movie stars of the first rank) and, let's face it, because of how old they are, Something's Gotta Give raises expectations as well as questions. Can they pull it off? Can these two still be sexy and romantic and funny enough to make us fall for this fairy tale about a couple of mature people who get it on and suddenly discover they never knew before what love is really all about? The answer is yes; there's a powerful, ageless chemistry at work here.

Although Nancy Meyers' sprightly script structurally follows the old, workable formula of boy meets girl, boys loses girl, etc., it is anything but conventional, dealing as it does--and none too subtly--with ageism and sexism and the glorious discovery that down-and-dirty lust can lurk within the loins of an uptight, 50-something, "turtleneck kind of gal," as Erica describes herself. But it's not just Harry who turns her on, for Erica has another and even more persistent suitor, the much younger doctor who's more than happy to make house calls. Keanu Reeves really does look struck dumb by infatuation with her.

Keaton is full-out fabulous. Nicholson is good, too--great, even, in a couple of scenes--but Keaton deserves both bravas and blown kisses for her funny and touching portrayal. The part was reportedly written with her in mind, and it certainly takes full advantage of Keaton's unique, sometimes kinky screen persona. Near the middle of the movie, she pulls off what has to be the most drawn-out, most hilarious and most beautifully orchestrated emotional breakdown ever seen on film.

Nicholson also gets to do what he does best: be a cad. Although he's currently a bit too beefy to look good in the lovemaking scenes, as always he exudes that old devilish charm from every one of his cholesterol-clogged pores. And he brilliantly transforms his male chauvinist into a gentler, kinder, more lovable kind of guy. Harry is amazed to learn that not all heart attacks are a physical phenomenon; love, too, can strike pain in the chest.

Because it's slanted toward an older audience, Something's Gotta Give may not be the box-office draw it should be. Too bad, for younger viewers would find in it, if they cared to, a great example of what witty and stylish romantic comedy used to be--way before Ben and Jen, before "Friends" and "Will and Grace", and even before Harry met Sally.

-Shirley Sealy