As Jack Manfred, the suave, jagged-faced casino dealer at the center of “Croupier,” actor Clive Owen proves to be powerfully unflappable — a working-stiff James Bond, whose understated intensity draws you into the movie and refuses to let you leave.

Jack is an aspiring novelist, and he narrates the film in the third person, as though “Croupier” were his novel. In fact, he takes the job at the London casino primarily because he wants to find material for a novel, and he soon finds the line between himself and the fictional (but autobiographical) Jake increasingly blurred.

Jack, for example, would never break the casino’s strict policies against fraternizing with fellow croupiers, or with gamblers in a non-casino setting. Jake, however, eventually does both, carrying on with the plain-looking Bella (Kate Hardie) and the apparently-rich patron Jani (Alex Kingston) — all to the distress of his girlfriend, Marion (Gina McKee), who is upset by his strange working hours and unsettling devotion to what was supposed to be a temporary job.

It’s not temporary, though: Jack is as addicted to watching people gamble as some people are to gambling. The extraordinary odds, the faces on the losers, the way they keep coming back for more — all of it is fascinating to Jack, whose keen eye for observing human nature sees this world as just the thing for his novel.

The plot thickens when Jani approaches Jack with a proposition to help her get out of a major gambling debt by letting some of her friends rob the casino. To say any more than that would be to spoil things, but I will say that there are twists and surprises in store in this very moody, engaging film. Nothing on the order of “Sixth Sense,” and nothing completely ridiculous; just some nice, eyebrow-raising developments that keep you interested in what is an engrossing movie to begin with.

B+ (; R, occasional harsh profanity, nudity, a couple sex scenes (without nudity), some fistfight violence.)