The Departed is an engrossing, entertaining film worth the trip to the theater (rather than the wait for the DVD). Leonardo DiCaprio is outstanding, Matt Damon perhaps at his best, and Jack Nicholson — well, Jack plays Jack Nicholson better than anybody else can. In lesser roles, Alec Baldwin and Mark Wahlberg win every scene in which they play. Vera Farmiga is appealing in the one female role; Martin Sheen plays Jed Bartlet playing a police captain.
Damon is a hoodlum who is undercover as a cop. DiCaprio is a cop who is undercover working for a hoodlum. Nicholson is the hoodlum. All these clashing male egos (performers and characters) are brought together by Martin Scorsese, who builds the tension on the screen and uncertainty in the audience. Is the bad guy getting good? Is the good guy getting bad? Is Jack Nicholson for real? Fans of Goodfellas will like this film, though it is darker, more complex and—unbelievably enough—considerably more violent.
NewMexiKen thought the film a bit long (about 2:20 before the credits rolled). And the ending seemed a trifle too contrived, but any discussion here would necessarily reveal too much, so see for yourself. Not for the faint-of-heart, but otherwise a very, very well-made movie.