So dark it’s almost criminal

One SUSPECTS, in the current climate, that the actor Adoni Maropis views the particulars of his visage as both blessing and curse. He’s got a hard brow and even harder jaw; piercing eyes; crisp, bushy eyebrows; a spherical, solid bald head; and a skin tone that allows him to play a range of ethnic backgrounds.

In other words, he makes a great terrorist. On “24” last year, he played Abu Fayed, the stern, persistent, always-angry head of a terror cell and significant antagonist to Jack Bauer.

So when he appears midway through the fourth-season premiere of “Criminal Minds,” 9 p.m. Wednesday on CBS, as a smiling, warm-hearted ambulance driver who arrives to help a wounded federal agent, it’s difficult not to feel a little impending dread. But this show routinely subverts its mystery by telegraphing its moves way in advance -- having Maropis in this role was just one tell among many.

Last season concluded with an SUV belonging to one of the show’s agents exploding, and the season premiere picks up immediately afterward. Two agents have been injured, and the rest of the team is scrambling to figure out the larger plan.

Ultimately, this episode aspires to be a larger commentary about how paranoia, post-9/11, is perhaps as much of a crippling force as terrorism itself. Because it has been determined that responders are the terrorists’ actual targets, all sorts of emergency response personnel set up camp a few hundred feet away from the explosion, waiting for the area to be screened for a second bomb. In other words, doing nothing becomes the only thing to do.

This is consistent with the tone of the popular series thus far, which is one of persistent gloom. Perhaps there is a sense of security in this show, in which the crimes that get solved seem more gruesome and less controlled than, say, those on “CSI.” It is like trauma porn.

And “Criminal Minds” is by far the most morbid of all the procedurals; a pallor appears to hang over each episode. Aaron Hotchner (Thomas Gibson) seems to float through each episode in ghoulish fashion, as if death were an inevitability (the heavy-handed quotes he delivers at the top of each episode -- this week it’s from Hemingway, about war -- don’t help).

Previously, he’d been balanced somewhat by Mandy Patinkin, who played the show’s most senior agent, Jason Gideon. A terrific actor, Patinkin had long managed to take the show’s almost unbearable gravity and inject moments of thoughtfulness and perspective. It might have been one of the least demanding roles of Patinkin’s career, but he played it sharply.

Patinkin left last year before Season 3 got into full swing, and Joe Mantegna, who replaced him (playing a new senior agent, David Rossi), hasn’t quite nailed that trick. And he doesn’t receive much help from the rest of the cast: as Derek Morgan, Shemar Moore projects a blank masculinity, and as Dr. Spencer Reid, Matthew Gray Gubler never quite lives up to the promise of his shaggy, graduate-student exterior. Even the show’s eccentric female technical wizard (an underanalyzed trend on procedurals), Penelope Garcia (Kirsten Vangsness), seems glum up against Pauley Perrette’s frenetic Abby Sciuto on “NCIS.”

Another of the terrorists in this week’s episode sums it up neatly: “Is that all you see, huh? Darkness?” He’s saying that to Morgan, who has chased him into an empty subway station. It’s an apt question on a show that thrills in violence’s cycles. Later in the episode, Maropis’ character has a cellphone detonator in one hand and a knife in the other. And even though four agents have guns drawn on him, no one pulls the trigger. To do so would almost break the mood.