I feel like an ingrate about The Departed, Martin Scorsese’s latest. Scripted by William Monahan, this is a cops-and-robbers melodrama that contains everything you want in a thriller: riveting action, sufficiently believable characters, steamy sex, a plot with entertaining twists, and a colorful milieu (Irish Americans in South Boston) rendered with zesty detail. So what’s not to like? Well...though this is a movie crammed with good things, it’s also a movie that feels crammed. What should have been a 100-minute entertainment has ended up as a 150-minute attempt at serious character study and moral analysis. To be sure, the suspense is never quite defused; several sequences will keep you on the edge of your seat. But neither is the film trim. The Departed is like an athlete who has spent as much time in therapy as on the playing field, and, with a layer of fat he can’t afford, shows as much strain as strength. The crowd applauds several brilliant feats but winds up feeling as exhausted as the athlete.

Yet I can well understand why Monahan and Scorsese felt their story needed depth as well as heat. Here is a tale of false fathers and betraying sons. There are two young Irish-Catholic protagonists: Colin Sullivan and Billy Costigan, both the products of fractured families. In his childhood, Sullivan (Matt Damon) acquires a dangerous father figure in the mobster Frank Costello (portrayed by Jack Nicholson as a Hibernian and therefore not actually based on the real Italian-American gangster who died three decades before this story takes place). Costello pays for the boy’s education and puts him through the police academy, so that when Sullivan becomes a plainclothes state officer working with an FBI task force in pursuit of Costello, the youth can tip off the mobster whenever the cops get too close. (And in his cell-phone warnings to Costello, Sullivan calls him by the code name, “Pop.” Nudge, nudge.)

Billy Costigan (Leonardo DiCaprio) is the converse of Sullivan. A former delinquent struggling to remake himself, Costigan gets recruited by the task force to place himself in Costello’s hire, and the gangster treats this youth, too, like an adopted son. So The Departed is the tale of two traitors, though one of them is on the side of the angels. As if that weren’t enough, Costello himself turns out to be a sort of mole. And, as if that weren’t enough, there is also sexual betrayal when a beautiful police psychiatrist (Vera Farmiga) living with Sullivan welcomes Costigan into her bed. And, by sleeping with a patient (Costigan’s work is giving him nightmares), she is also betraying the ethics of her profession.

So, betrayal within betrayal within betrayal. Potentially powerful stuff. But many of the scenes meant to give psychological depth to the material seem labored or showy or merely vacuous, even when they are well acted. Vera Farmiga’s fascinating face (Whistler would have begged her to be his model) conveys the tensions of a woman whose lofty education hasn’t prepared her for men living in a perpetual feeding frenzy, but, though her initial encounters with her two lovers are well written, neither affair develops in an interesting direction or reveals anything interesting about the two men or herself. (The suggestion that Sullivan’s inner turmoil has made him impotent while the even more nerve-wracked but virtuous Costigan performs satisfactorily belongs strictly to the annals of movie-movie psychology.)

Scorsese has put just enough of a lid on Jack Nicholson to make Costello a viable demon instead of a Nicholsonian hoot, but his dialogue is standard gangsterish gloating. (“No one hands you anything. Ya gotta take it.”) And making this thug a reader of James Joyce and an opera aficionado is an example of jazzing up stale material instead of discovering the truth within a stereotype. Compare the writing of the Nicholson-DiCaprio scenes with the ones Paul Attanasio wrote for Al Pacino and Johnny Depp in Donnie Brasco and you’ll see the difference between pretension and veracity.

Worst of all, the scenes of feuding and one-upmanship between the state officers and the FBI agents are so repetitive and uninventive in their macho profanity—the F-word has become the most boring monosyllable ever uttered on a movie’s soundtrack—that a mere trimming of these scenes would, I feel, have given a lift to the entire movie.

Yet Scorsese remains a master of tension and ferocity. His torture scenes make one cower inwardly. His shootouts have the messiness of real-life violence. And he has managed (better than any other action director I know of) to incorporate the latest technology into the standard melodramatic patterns of eavesdropping and pursuit. There is a scene here—Sullivan and Costigan hunting down each other in Boston’s Chinatown—which brings into play cell phones, caller I.D., and video cameras, none of which come across as mere gizmo showiness (as happens in a James Bond film) but rather as surveillance employed to lethal ends. Another scene has the two enemies listening to each other’s breathing on their cell phone, while neither dares speak for fear of revealing his identity. Not just the men but the very phones seem to be spying on one another.

Scorsese and his longtime editor, Thelma Schoonmaker, play upon the viewer’s nerves superbly by bringing the bustle and violence in certain scenes to a boil, cutting off the action abruptly for a moment of silence, then, with a change of camera angle and an aural jump into more noise, suddenly leaping forward to another boiling point.

Scorsese began his career as a highly idiosyncratic independent filmmaker who often depicted violence only because violence was a part of the world of his characters. Taxi Driver and Mean Streets climaxed with stunning scenes of bloodshed, but the substance of these films wasn’t violence but the nature of people who headed toward violence. In Raging Bull, a portrait of a professionally violent man, a boxer, Scorsese dared to conclude with a twenty-minute sequence that contained virtually no violence, because the hero’s brutality had burned itself out and his nature had changed. In all these films, scenes of tenderness, compassion, and humor were as memorable as the ferocity. Not so in the director’s latter-day string of gangster films (Goodfellas, Casino, Gangs of New York). Here one feels the milieus and plots were chosen to guarantee the violence. Characterization isn’t completely lacking but it is subservient to the gore. To be sure, Scorsese still makes movies such as The Age of Innocence and The Aviator in which characterization rules, but he seems to be underwriting them with the goombah epics in which his genius surfaces only by fits and starts, though the fits and starts can be unforgettable.

Related: Richard Alleva reviews Scorsese's 'Shutter Island'