There’s just one cemetery in Scott Frank’s “A Walk Among the Tombstones,” but it features plenty of tombstones. Liam Neeson even walks among them. Other people do, too, and there may or may not be a pivotal action sequence that takes place at said cemetery, most definitely among tombstones, with plenty of shooting and running to go alongside the walking (okay, there definitely is one). The title of the latest “hey, Liam Neeson is good at killing people” feature may be surprisingly straightforward, but the film’s content is genuinely unexpected: Liam Neeson is good at killing people, but yeah, he can totally follow investigatory procedure before he does it.

“A Walk Among the Tombstones” isn’t “Taken” or even “Taken 2” or “Non-Stop,” Neeson’s Matt Scudder doesn’t have anything personal on the line, he’s just an unlicensed private investigator with a slightly muddled police officer past who occasionally does “favors” for “friends” for “gifts.” If you need something taken care of that, for whatever reason, can’t involve the authorities, Scudder is your guy. He’s good at it, he’s dependable, and he’s got enough of a moral code to set himself apart from the rest the scum out there.

The crimes at the heart of “A Walk Among the Tombstones” are particularly trying, hard, heinous stuff – the film’s opening credits stealthily and steadily let on what’s ahead of us, featuring close shots of a woman in apparent ecstasy, being touched and caressed by what looks to be a caring lover. Except, oops!, she’s a captive and there are two guys touching her and, no, no, none of this is caring and loving and, yes, it’s okay to feel a bit queasy. Turns out, she’s not the only one, and Scudder’s services are soon requested by the smooth-talking Kenny Kristo (Dan Stevens), the brother of Scudder’s AA pal Peter (Boyd Holbrook, doing a lot with a little), who has lost his wife to the same creeps who molested the ill-fated star of the opening credits.

Scudder is initially reticent to take on the case – Kenny is a drug dealer, and even though Scudder deals with people who aren’t necessarily on the up-and-up at all times, he’s got enough sense to stay away from this one. Until, well, he just can’t, thanks to a teary Kenny who begs Scudder to take the case, punctuating his plea with the gory details: some dudes took his wife, they asked for a hefty ransom, he paid it, they killed her anyway. Mrs. Kristo isn’t the first victim of the two perps (David Harbour and Adam David Thompson, who are revealed early enough, the question of “A Walk Among the Tombstones” is never really “who,” but more “why” and “how”), and Scudder sets about finding the connective tissue between their victims in order to properly ID them and stop them before they kill again.

Oh, and they’re ready to kill again.

Set in 1999, “A Walk Among the Tombstones” is riddled with references to Y2K and all the outsized fears that came with that. Based on Lawrence Block’s novel of the same name, the film is preoccupied with people fearing the wrong thing – at one point one character even mutters, “people are afraid of all the wrong things.” A latent fear of someone kidnapping and murdering your loved ones because you’re a drug dealer might not be a common fear (or, really, a reasonable one), but Frank sells it, and “A Walk Among the Tombstones” is scary and unnerving in the best ways.

Scudder has secrets, like why he left the force and why he stopped drinking and why he doesn’t have a wife, and most of those answers are dutifully doled out throughout the course of the film, if not narratively original, at least necessary enough to be included. Frank’s screenplay occasionally hedges to obvious narrative movements, most of which he unexpectedly subverts at the last minute. Even the inclusion of a young, fun sidekick (Brian “Astro” Bradley) feels fresh, and Bradley’s TJ is compelling and interesting on his own (alongside Neeson, it’s nearly magic, someone give these two a sequel ASAP). Even better, the film has a tidy sense of humor about itself, and its heavy stuff is often punctuated by gut-busting giggles (Scudder, in the presence of a possible perp, says without a lick of irony, “You’re a weirdo, Jonas,” but we still know that he and Frank are going for laughs here, and does it ever work).

Still, Frank’s film is much more of a noir outing than a straight action feature, and Neeson slips right into the tone and feel of the hard-boiled detective offering. Neeson may have been treated to a big career resurgence thanks to his knack for big action, but he’s great as Matt Scudder, and the darker charms of the film suit him wonderfully.