At the beginning of The Pledge, Reno police detective Jerry Black (Jack Nicholson) is being given a retirement party by his friends in the department when a call comes in and several of his colleagues have to leave the festivities. Jerry volunteers to come along, but is told he doesn't have to. "Ahhh, I've still got six more hours...," he replies.

In the snowy mountains outside of town, they find the remains of a young girl who has been so badly mutilated that the officers who are already there can't figure out how they are going to convey to the news to the dead girl's parents. Jerry, who has had some experience in these matters, volunteers to perform the duty, but when he does so, the response by the girl's parents (Michael O'Keefe and Patricia Clarkson) affects him to the point where he assures them, committedly, that he will see to it that whoever did this terrible crime will be brought to justice.

Almost immediately afterward, a younger detective, Stan (Aaron Eckhart, back giving his Grade-A, number-one louse performance), interrogates a suspect who was seen near where the murder was committed. Mentally handicapped (and played, in unnervingly accurate fashion, by Benicio Del Toro), Stan delivers a confession from him, but Jerry is not convinced. "No offense," Stan tells him, ."..but you're retired. You don't work here anymore."  Only Jerry turns up evidence of a second, then a third, child murder, all previously committed, similar, and all unsolved, and he understandably  finds his associates' eagerness to "close" the current case off-putting. He made a promise, Jerry tells his department chief (Sam Shepard), adding, "You're old enough to remember when that meant something."

Whether a subsequent comment by Stan -- "Get a life!" -- is meant to be directed at Jerry or not is left tantalizingly unclear. The odyssey that Jerry sets out upon shows us the little bits and moments that go towards only further tacking-down a determination such as the one Jerry has taken upon himself. The cavalier attitude of a cop (Costas Mandylor) in another town who confides that crime scene photos no longer affect him to any degree. A revelation, from the grandmother (Vanessa Redgrave, who is quietly and absolutely wonderful) of the most recent victim, about a story that was the girl's favorite -- "She loved Anderssen," the woman says, referring to the story's author, Hans Christian Anderssen. Then there's a moment when the father (Mickey Rourke) of another victim disassembles, showing his feelings nakedly about the murder, before quickly pulling himself back together.

Jerry even turns what should have been his inaugural retirement vacation, at a prime rural fishing spot, into a stakeout, buying a gas station located in the nexus of where the three killings occurred. There is even some measure of domestic tranquility with a local waitress, Lori (Robin Wright Penn), and her young daughter, Chrissy (Pauline Roberts), who turn out to be in need of some protection already. The way in which the film handles this unusual transition, which considerably extends the timeframe of the story,  is remarkable -- it could easily have shattered the picture's hold on us -- but the story, and Nicholson's performance, deepens instead, as we see how everything fits in with Jerry's consistent vigilance towards the person whom he is intent on capturing.

He suspects that a local man could be it -- played, in an obvious bit of casting, by Tom Noonan, who I had thought had left these kind of typecasting roles behind when he played his psycho-killer-to-end-all-psycho-killers in Last Action Hero. His character fits the profile that Jerry has assembled of the perpetrator, and he talks to Chrissy on more than one occasion. The picture shows, unnervingly, that the way Jerry talks to Chrissy is not all that different from the way the killer would, except that while we are thoroughly convinced that Jerry is good (and he is indeed a good person), there is no way that a young girl like Chrissy could distinguish whether she is being taken into the confidence of a demon or not.