In South Boston, Irish crime boss Frank Costello (Jack Nicholson) takes special attention in a neighborhood kid who grows up to be Matt Damon, playing a cadet for the Massachusetts State Police named Colin Sullivan.

With his connections, Sullivan rises quickly in rank to detective, and joins a Special Investigation Unit led by Alec Baldwin that’s assembled to take down Costello. Acting as the crime boss’ mole in the task force, Sullivan is able to keep Costello and his thug flunkie Mr. French (Ray Winstone) one step ahead of the investigation.

Martin Sheen and Mark Wahlberg run undercover operations and hand pick a police cadet named William Costigan (Leonardo DiCaprio) – who has questionable character and family from South Boston – to briefly serve prison time, have his record doctored and infiltrate Costello’s gang.

While cool on the surface, Costigan starts to unravel, convinced Costello will expose and kill him at any minute. He goes to see a police therapist, played beautifully by actress Vera Farmiga in a star making role. But the shrink’s boyfriend is … Costello’s mole, Sullivan.

Directed by Martin Scorsese, from a screenplay William Monahan adapted from the Hong Kong cops and robbers flick Infernal Affairs, The Departed sets a high bar for itself. DiCaprio, Damon and Wahlberg share the marquee with Jack Nicholson, back playing a villain. This is the fourth crime film from the director of GoodFellas and Casino, so to say that Scorsese knows this turf well should be an understatement.

Even if I accept that this is a plot driven remake of a Chinese popcorn thriller, not a gangster epic of the class Scorsese has given us in the past, it didn’t work for me. It struck all kinds of false chords very early on and never recovers.

The logline is brilliant: DiCaprio and Damon play imposters, both trying to fit in where they don’t belong, both trying to smoke each other’s bullshit out, and both aware that failure means getting wacked by Nicholson, who ironically, represents the father neither one of them had.

But to make that work, you need a tremendously sophisticated screenplay – one that delves into the worlds of the Irish mob and the Massachusetts State Police – that movies rarely, if ever, possess anymore. The Sopranos and The Wire are doing it on HBO, but they have 12 hours to tell their crime sagas each season, and a staff of writers on the payroll to do it.

Here it’s William Monahan, who wrote a remarkably underrated medieval epic for Ridley Scott called Kingdom of Heaven, but The Departed never rises to that level. It plays down to the level of an English language remake of a Hong Kong import, or worse, a video game.

The guy you’re paying to see go off – Nicholson – is surprisingly subdued and mostly grounded throughout the film. Mark Wahlberg and Alec Baldwin’s characters have ridiculous, “Are you shittin me Pyle?” half page monologues that shoot up into the sky like fireworks, and fizzle. The Irish are bound to be cheesed off that they still haven’t been given a modern gangster film about themselves that’s anywhere near as defining as GoodFellas.

DiCaprio and Wahlberg do outstanding work, once more proving that they’re both among the best leading men of their generation, though the ladies might have an issue with the Supercuts hair Wahlberg’s character sports in this one. Vera Farmiga, who could have easily been a trophy female getting tugged on, brings an academic pedigree and an intriguing vulnerability to her character that really surprised me. Expect a lot of directors wanting her in their films following this one.

When the movie gets going – as when DiCaprio tails Nicholson to a meet with Damon in a porno theater, but barely misses spotting the rat – this is highly competent thriller moviemaking. But honestly, those moments are few and far between. The final 20 minutes are just an orgy of one guy getting his brains blown into guacamole by another guy, until only two of the picture’s cast members are left standing.

I realize this is a popcorn thriller, an entertainment vehicle, but since I never believed that this movie took place in Boston, dealt with gangsters or cops, or reality, I ceased to give a shit.