A remake of the 2002 Hong Kong thriller Infernal Affairs, The Departed has been championed as Martin Scorsese’s throwback to his gritty gangster roots, but despite a top-drawer cast of Leonardo DiCaprio (Scorsese’s current muse), Jack Nicholson and Matt Damon, and terrific source material, the film doesn’t add up to much more than the sum of a few very good parts. It’s not a dud by any means -- it’s often entertaining and amusing. It’s just rarely emotionally gripping and ridiculously overlong. The script by William Monahan mostly retains the original’s mole-vs-mole hook, while fanning out certain characters and tweaking a few areas here and there (including a lousy change to the ending). As with any Scorsese pic, The Departed opens great, with sharp, fluid direction that ushers the viewer into the narrative effortlessly. A few things in Scorsese’s version work better, such as the psychiatrist-romance angle, and the more realistic locations. But as the film progresses, and Nicholson’s presence becomes more pronounced, things begin to fumble. The surprisingly sloppy scene transitions, cringe-worthy soundtracking, and overly goofy tone draw us away from what is ostensibly the film’s main attraction: the ingenious cat-and-mouse plotting. Damon is at his two-faced, sociopathic Ripley-est as Sullivan; DiCaprio hasn’t lost enough of his babyface to fully convince as a tough guy, but there’s always a stormy conviction at play here that suits his character. The larger-than-life Nicholson, undoubtedly a contributor factor to the bloated running time, so insistently overshadows everyone in the film with his wolfish grin and bizarre tics, it nearly amounts to bullying.