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Thank heaven for Martin Scorsese.

In his latest flick, "The Departed," a Warner Brothers entry which is rated R and yet another U.S. remake of a Hong Kong hit, Leonardo DiCaprio plays Billy Costigan, a tough kid turned Massachusetts state detective who goes undercover to infiltrate Jack Nicholson's Irish mafia.

Nicholson, being as sly onscreen as he is off, has a mole within the State Investigation Unit, Colin Sullivan, played by Matt Damon.

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Sullivan is a dangerous opportunist rising in the ranks of the state's elite police force, but who would sell out his own mother for Nicholson's Frank Costello.

While working both sides of crime and punishment to do his master's bidding, he puts the good guys unnecessarily in harm's way, including Martin Sheen and Mark Wahlberg — who is so good in this movie you end up wishing he had more screen time.

Alec Baldwin rounds off this star-studded cast as an FBI liason.

While every actor and actress turns in a terrific performance — and no matter how much we've been hearing about how great Nicholson is here — this movie is most definitely DiCaprio's.

DiCaprio's good looks have matured in each movie he's done since he wowed audiences and Hollywood in 1993's "This Boy's Life" opposite Robert De Niro.

While he was once best known for making teen girls swoon in "Titanic," it is clear that DiCaprio is all grown up, and moviegoers — both men and women — are the better for it.

Dare I say DiCaprio's undercover cop is better than Johnny Depp's "Donnie Brasco," and I say that with the utmost respect to Depp. That's how good Leo is here.

Now take this talented cast, add the beautiful and understated Vera Farmiga ("The Manchurian Candidate") as a love interest of two of the central characters, and put Scorsese as a cherry on top, and you've got yourself an extremely satisfying movie-going experience.

Keeping It Reel?

"The Departed" is not "Goodfellas," but it's darn close, and it brings gangland impresario Scorsese back to what he does best. Kill, and kill again.

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