'PLEDGE' KEEPS PROMISE TO BE FINELY DIRECTED, ACTED.

Byline: Bob Strauss Film Writer

Sean Penn's third outing as a director, ``The Pledge,'' shows him growing into the job - slowly, like his movie is paced, but unquestionably improving and exhibiting greater command of his filmmaking tools.

Which is not to say that ``The Pledge'' is any more entertaining (nor, in the long run, more insightful) than ``The Crossing Guard'' or ``The Indian Runner.'' But it is a better-wrought piece, with Jack Nicholson delivering the best performance Penn's ever directed, which is quite strong praise.

Nevertheless, this is another grim story about murdered children and life-shattering obsession that, once again, provides ample evidence that Penn just doesn't know when to quit. It's not deep enough to leave even those who can take it wowed, but what's good about it can be very good.

Although Nicholson drives the piece with an understated, quietly roiling performance that's the most natural work he's done in at least a decade, several other actors, not surprisingly, also register brief shining moments. But for every perfectly pitched appearance - Aaron Eckhart as a cocky young detective more interested in resolving a case than actually solving it, Helen Mirren as a psychiatrist with swift and pointed perception - there's a role that's either way overcooked (Benicio Del Toro's mentally handicapped Indian) or short of the mark (Sam Shepard, doing a police captain as by-the-book as the other cop figures are distinctively original).

Nicholson's Jerry Black is an unmarried Reno detective who likes to fish and work and have a few drinks, pretty much in that order and to the exclusion of most else. Admired by his colleagues, who chip in to send him off to Baja as a retirement gift, he at first appears content with the prospect of reducing his life to just two central activities.

But his last night on the job, Jerry works the rape-murder of a little girl. He's the only one with enough guts to break the news to her parents - an astounding scene that Penn stages in a vast barn full of young, cackling turkeys - and they make Jerry vow to find their daughter's killer.

Before he can fulfill the mission, though, young partner Stan (Eckhart) solves the case ... to everybody's satisfaction but Jerry's. Doing a little research on his own, Jerry detects a pattern of similar crimes in the mountain communities outside of Reno. His former colleagues find Jerry's evidence slim at best and dismiss his pleas to re-open the case as a form of job-partem dementia.

They don't know the half of it. To catch his phantom criminal, Jerry completely changes his life, relocating to a rural crossroads where he buys a gas station in hopes that the real killer will drive by. Months, perhaps years, pass - as we said, this film unfolds slowly - and during the time Jerry develops a rewarding relationship with abused local woman Lori (Robin Wright Penn) and her delightful young daughter, Chrissy (Pauline Roberts).

At a certain point in the film, you think that Jerry and, perhaps, even Penn have forgotten about the murder mystery, so detailed is the care with which the detective's new life is illuminated. You've never seen Nicholson more tender than in some of the parenting scenes with the girl, or so vulnerable as when the troubled Lori eventually reaches out to Jerry for something more than help.

But the cop's obsession never goes away. And when it's triggered, the damage is appalling.

Appalling but, really, kind of predictable, even if so much of the moment-to-moment behavior in the story is not (the film was adapted from a novel by Friedrich Durrenmatt, a Swiss existential playwright who wrote the book as a kind of protest against the mechanical nature of the mystery genre). Penn sets an oppressive overall tone from the beginning, so we just know that things aren't going to turn out well. And as great as Nicholson's performance is, it's too much of a good thing for the narrative's sake. It's like Penn loathed the thought of cutting a single one of Jack's brilliant gestures, but leaving them all in builds a head of fatalistic repetition.

But then, if any film star has earned a movie's worth of indulgence, it's Nicholson. And what he gives us here is offered with a kind of becoming humility, free of the bombastic technique that marks much of his recent work. If only for creating a much finer showcase for Jack's genius than he did in ``Crossing Guard,'' Penn has broken through to a new level of directorial achievement.

``THE PLEDGE''

(Rated R: violence, language, children in jeopardy)

The stars: Jack Nicholson, Benicio Del Toro, Aaron Eckhart, Helen Mirren, Robin Wright Penn, Vanessa Redgrave, Pauline Roberts, Sam Shepard, Harry Dean Stanton.

Behind the scenes: Directed by Sean Penn. Written by Jerzy Kromolowski and Mary Olson-Kromolowski. Based on Friedrich Durrenmatt's novel. Produced by Michael Fitzgerald, Sean Penn and Elie Samaha. Released by Warner Bros.

Running time: Two hours, four minutes.

Playing: Citywide.

Our rating: Three stars