An undercover cop infiltrates the inner circle of a feared Boston mobster, unaware a senior fellow officer is an informant on the gangster's payroll. When the crooks and the police both realise there is a mole in their ranks, the two detectives are in sudden danger of getting caught - and one of them has to be the first to expose the identity of the other man in time to save himself. Martin Scorsese finally picked up an Oscar for this cracking thriller, having been ridiculously ignored by The Academy for so many years, despite helming classics like Raging Bull and Goodfellas. Whilst this is not on the same lofty level as those aforementioned classics, but is still a tense, superbly directed, wonderfully acted thriller. Leonardo DiCaprio, Matt Damon, Jack Nicholson and Mark Wahlberg are the all star cast, while Ray Winstone manages to steal every scene he's in.