May 18, 2001 | About 45 minutes into Angel Eyes, a riveting drama about wounded hearts and second chances, I was struck by the sudden realization that I had no idea where the movie would be going next. Better still, I knew that, wherever it did go, I wanted to follow. Trust me: In an age when most mainstream movie plots are simplistic enough to be synopsized in 30-second TV spots, unpredictability counts for a lot. The only downside is, there isn't a lot I can say in regard to what's so special about this particular scenario, because so much of the film's impact depends on the element of surprise and the upending of expectations.

Uncommonly compelling and exceptionally well-acted, Angel Eyes is - on one level, at least - a haunting, heart-wrenching love story. A prologue introduces Sharon Pogue (Jennifer Lopez), a Chicago police officer, as a sensitive soul who does her darnedest to rally a seriously injured driver in the wake of a terrible auto mishap. Lest we mistake her for a softie, however, the film flashes forward a year to show that, in the line of duty, Sharon can talk just as tough as her male colleagues, and act even rougher when she gets angry. She gets angry a lot.

Sharon is very nearly killed while chasing an armed suspect. Just in the nick of time, though, the thug is disarmed by a passing stranger who identifies himself as Catch (Jim Caviezel). He says he just happened to be in the right place at the right time. But, then again, there could be more to it than that.

(With his borderline-shabby attire, his perpetually spooked-out expression and his inexplicable urge to be a selfless do-gooder, Catch initially seems like the twin brother of the street person Caviezel played in Pay It Forward. You can't help imagining that the actor simply walked off the set of that movie and onto the set of this one.)

Understandably curious about her savior, Sharon probes and prods during extended conversations. (She admits, only half-jokingly, that even when she's off duty, she can't repress her instinct to interrogate.) But Catch says little, and reveals less. Mostly, he smiles and remains nonjudgmentally silent while Sharon - eager, perhaps desperate, to confide in a sympathetic stranger - talks about the root causes of her anger. About the time she arrested her abusive father (Victor Argo) after he beat her mother (Sonia Braga) once too often. About how, ever since, she - not her father - has been estranged from her family. About how her married brother (Jeremy Sisto) appears to be continuing the cycle of domestic violence.

One thing leads to another, Catch and Sharon become lovers. But even then, Sharon knows next to nothing about this guy whom her partner (Terrence Howard) aptly describes as "a ghost." He doesn't mean that literally, of course. He's simply referring to the conspicuous lack of information about Catch in any police or government data banks. Maybe Catch isn't whom he says he is. Or what he says he is. And if so, then maybe.…

OK, that's all you need to know about the set-up. The pay-off is a bit anticlimactic - this is one case where the journey, not the destination, is the most important thing - but it's nonetheless dramatically and emotionally satisfying. Just as important, it flows logically out of the clues and hints we're given early in the game. Don't misunderstand: Director Luis Mandoki and screenwriter Gerald DiPego, who last teamed on Message in a Bottle, aren't trying to pull a Sixth Sense switcheroo. But they succeed splendidly at making Sharon and Catch sufficiently complex - and more than a little mysterious - to capture our interest and win our sympathy.

In her best movie performance to date, Lopez illuminates the many facets of her character with emotional truth and megawatt star power. But wait, there's more: She also continues her proud rebellion against contemporary standards for female beauty in mass media. When she strips to her underwear to swim in a park lake, she looks radiantly robust - to use Charles Bukowski's memorable phrase, like "a womanly woman" - and not fashionably underfed. Good for her.

Caviezel has the trickier role, since he has to keep so much bottled up for so long. He, too, makes a winning impression, playing Catch in a style - equal parts weary sadness and boyish whimsy, spiked with a hint of muffled rage - that recalls a young, pre-Psycho Anthony Perkins.

Much to their credit, the makers of Angel Eyes resist the temptation to explain or settle everything. At the end of the movie, at least one major conflict remains unresolved, and one of Catch's defining eccentricities remains unexplained. You can read that ambiguity as a roundabout compliment. Obviously, Mandoki and DiPego feel that we're smart enough to sort things out for ourselves.