With a cast that includes some of Hollywood's heaviest hitters, one would expect the 2006 crime drama "The Departed" to deliver the goods.

And it does. On a number of different levels.

The violent film, directed by first-time Oscar winner and legendary filmmaker Martin Scorcese, works as an intense thriller, and combines elements of drama, comedy and romance into a two-and-a-half-hour masterpiece.

From the moment that veteran actor Jack Nicholson begins narrating the story, the viewer is hooked. At least this viewer was.

And remember parents, the R-rated movie is chock full of violence and bad language, so you might want to think about putting the kids to bed for this one. In fact, that's the best thing to do.

The film's ensemble cast also stars stellar actors Leonardo DiCaprio, Matt Damon, Mark Wahlberg, Alec Baldwin, and Martin Sheen, all of whom have been cast perfectly in their respective roles, and most of whom seem to have perfected their craft.

A host of other actors and actresses provide the final piece to the near-perfect puzzle that is this film.

DiCaprio and Damon are spectacular, while Wahlberg (who received an Oscar nomination for his performance), with his aggressive performance, proves once again why making the move to Hollywood was the best career choice he could have made.

Baldwin (a foul-mouthed police captain) and Sheen (the straight-laced detective), both veteran actors in their own rights, add a balance to the mix of youthful actors they share the screen with. If anything, it is possibly the most serious, yet most humorous performance that Baldwin has ever given.

The story takes place in modern-day Boston, where we see 30-something rookie police officers Billy Costigan (played by DiCaprio) and Colin Sullivan (Matt Damon) graduate from the police academy. Sullivan will go on to success in the Special Investigation Unit, while Costigan, who has lived a life of crime up to this point in his life, is chosen by his superiors to be a mole who must investigate the inner workings of the Boston Mafia and big-time crime boss Frank Costello (Nicholson).

Costigan must earn Costello's trust by proving to be a loyal soldier in the mob, while Sullivan, who grew up in the neighborhood with Costello serving as his father figure, plays the part of a "rat" himself, tipping off Costello about police investigations into his activities and withholding information from his own colleagues.

What's interesting to watch here is how both men's dangerous lives begin to take their toll, slowly chipping away at each other's integrity and sanity.

The film follows the on-going activities of our primary characters, and as the story unfolds with plenty of plot twists and turns, both moles become aware of each other and are led down a course where their paths must eventually cross.

A love interest for both main characters, a criminal psychiatrist played by actress Vera Farmiga, is thrown into the mix to add a sense of morality and self-deception to the tale. Not only are our main characters lying to themselves and their co-workers, they must also ask themselves if it acceptable to lie to the ones closest to them.

The film's story builds toward a dramatic climax, as the viewer watches Costigan and Sullivan blend into their environments, betraying people every step of the way. The viewer becomes almost infatuated with who will succeed by film's end.

And finally, after the credits roll, the bigger question could be, "Has anyone in the film succeeded?" A fitting question, even if Costello should be apprehended by the end of the story, when everyone knows that life and crime will go on, even when some criminals are brought to justice.

Just one of many questions viewers might be asking themselves after watching one of the best thrillers in recent memory, and one of Scorcese's best films to date.