There's a moment in Training Day which, if the viewer takes it the wrong way, can stretch the credibility of the story. But if accepted as a legitimate event within the tale being told, its beauty will unfold. I won't reveal it here, but for me it's the defining moment of the movie. Its message is clear: pure acts of good are rewarded. Acts of corruption are not justifiable.

It is poetic how the movie sets up for that moment and the ensuing sequences confirming that message. From the beginning, the movie's resident serpent, veteran LAPD narcotics officer Alonzo Harris (Denzel Washington), dangles the temptation of corruption before Jake Hoyt (Ethan Hawke), the rookie he is training on their first day together. Jake is the embodiment of the innocent greenhorn, a cop who wants this job so that he can rid the streets of the drug dealers--the "poisoners," as he calls them. But the lessons he gets from Alonzo aren't so simple. Petty drug pushers are disregarded in favor of only going after the big fish. In order to get the big fish, rules must be bent and, as the movie's ads suggest, lines must be crossed. Is this right? Do lesser evils have to be committed in order to achieve a greater good?

For the longest time, the audience rides through this dilemma along with Jake. He follows Alonzo's orders and witnesses his actions with obvious indignation, but his lack of experience and street knowledge feeds his doubts. After all, Alonzo is persuasive, driving through gang-infested streets as if he owned them, exhibiting a combination of confidence, intelligence, self-assurance, and smoothness that can only be described as bad-ass. He makes the code by which he operates look defensible, however immoral it may be. During the course of the day, though, Jake will find out just how much of a devil Alonzo truly is.

It's been a long time since I've watched such an entertaining story. Screenwriter David Ayer's script is so packed I'm amazed everything plays out in only two hours. Jake and Alonzo are given ample dialogue to flesh themselves out, and they still have time to participate in one harrowing event after another. Jake's training day emerges as the stuff of nightmares, where every bad thing that could happen will happen, and all the while the viewer is hooked. Much of the credit for that goes to director Antoine Fuqua, who shot the film on location in urban Los Angeles. From using overhead shots of the freeways to actually filming in the notorious "Jungle," Fuqua creates a picture of L.A. that feels menacing and dangerous, giving the proceedings a realism that helps  heighten the tension of the situations faced by Jake, and therefore fully involving the viewer. Fuqua also pulls no punches in depicting violence and its aftermath, which only adds to the intensity.

Elevating the film's quality even further are the performances of its two stars, Washington and Hawke. Washington, usually cast as a good guy, is fully convincing as the snaky Alonzo, a man who believes nothing can touch him. Washington clearly relishes this chance to play a character who can simultaneously inspire awe and disgust from the audience. To complement Alonzo's overbearing presence, Hawke gives Jake just the right amount of naivete, which is not too much and not too little. His facial expressions alone show the conflict raging within him, asking himself whether or not he can trust his mentor. Both actors bring believability to their roles, and it's a pleasure to watch them.

Training Day may feel a little exaggerated at times, but it comes with the territory of telling a story that's larger than life. It has chosen a simple yet enduring theme. When told well, few things are as satisfying as a classic tale of good vs. evil. In this movie, evil seems all too strong, even sensible, until the moment I mentioned earlier occurs. Think back to what led to that moment, and think about what it is saying -- what every solid good vs. evil story should say: no matter how much evil tries to corrupt you, the spirit of good will be your salvation.

(Released by Warner Bros. and rated "R" for brutal violence, pervasive language, drug content, and brief nudity.)

Review also posted on www.windowtothemovies.com.