I'm sitting in a $35,000 Bouvier hydrotherapy tub, up to my neck in a nice warm consommé of algae. The lights are low, the candles are guttering, and all that's on my plate for the rest of the day is this two-hour treatment--yet I'm peppering my therapist, Suzanne DeFranco, with questions about the bath, the resort, and the Surrender Retreat, which I am halfway through without yet having capitulated. (It's just temperament, not dissatisfaction.) Suzanne, who is mine for the duration (four days), has been forbearing, the patient mother indulging the child who won't go to sleep. But now she lays down the surrender terms. Leaning in close, she says, "If you'll just relax and give yourself over emotionally to this, I'll answer all your questions when we're done."

And with that, I raise the white flag.

Like going to live on a South Seas island or intelligently disposing of jackpot lottery winnings, letting a spa "just take care of you" is not as easy as it sounds. I am accustomed to having a say in my life--I suspect Spa Montage's clientele is, too--and the habit doesn't disappear just because a spa says, "Leave it to us." But getting you to drop your guard, furlough your need for control, let their fingers do the walking--that's the gist of the nearly one-year-old Surrender Retreat at Montage, the 262-room resort on a spectacular bluff-top perch in Laguna Beach, California, about an hour south of Los Angeles. The four-day program is offered four or five times a year.

The Surrender Retreat combines the workout and therapeutic regimens available at destination spas such as Canyon Ranch with the luxury pampering that is the stock-in-trade of resort spas. It's on the forefront of one of the biggest spa trends today, customizing the guest experience. And it shows just how congenial a roost fitness, wellness, and relaxation have found in luxury resorts--and this is a very good one, indeed.

Surrender grew out of spa director Barbara Schultz's conviction that the traditional spa menu is more impediment than expedient. Guests don't understand many of the treatments (and don't ask about them for fear of looking green), much less have the self-knowledge necessary to determine which treatments would work best for them. Moreover, the spa menu tends to promote superficial interaction with the spa staff, the sort of conversation you might have at a Häagen-Dazs store. ("What does that treatment taste like?") The result: Guests default to plain vanilla (a.k.a. Swedish).

That's why Surrender seeks to sideline the menu by catching the guest before and upon arrival. (Schultz would like to drop the menu completely but fears that could result in mere spa-narchy.) A week or so before a participant arrives, one of the spa staff calls to do a preliminary assessment and get the guest to think about what he would like to accomplish. Once at the spa, he goes right into "Art of the Spa," a one-hour hot-cold hydrotherapy session designed to jump-start the circulation and flush out the system, followed by a two-hour Aroma-Balancing session in which reflexology, dermal-zone, and lymphatic-drainage techniques are used to pinpoint problem areas and organs that are out of balance. ("Balance between organs equals good health," says Suzanne.) On day one there is also a fitness assessment. Out of these sessions comes your program, which includes two hours of spa treatments and two hours of fitness training daily.

As for handing over the keys to your self, "some people take a good day and a half," says Schultz. "Some arrive already there." But terminal type A's take note: For you the spa suggests the Laguna Beach Kur as the overture--a warm mustard-seed hydrotherapy bath followed by a wrap in a sheet soaked in ice water. "It immediately puts the person in a relaxed state because the body slows down to warm up," says Schultz. "They often conk out."