"You don't understand," Detective Sergeant Ellie Miller insists as she stares at a murdered child on the beach of the sleepy town she calls home. "I know that boy!"

Miller is one of the two heroes of "Broadchurch," a British crime series making its BBC America debut tonight at 10 p.m. Played by Olivia Colman, she's a Broadchurch lifer. She knows everyone in town, and assumes she knows everything around them; it's not possible that any of her friends or neighbors could be a killer. And yet as her partner and boss, new transplant Alec Hardy (David Tennant) keeps reminding her, anyone can become a killer, and the sandy corpse of young Danny Latimer is proof of that.

It's a simple conflict, and "Broadchurch" for the most part is a simple series. Over the course of eight episodes, we follow the Latimer case from its terrible beginning to its complicated ending, as Hardy teaches Miller about all the secrets her friends and neighbors have been keeping. The writing by Chris Chibnall is lean and spare, and the directing (most of it by James Strong) takes advantage of the seaside vistas without calling attention to itself. Other than an interesting minor subplot about a phone company technician who claims to be a psychic, this is as straightforward a mystery series as you can imagine.

It's also about as devastating as you can imagine, precisely because of that simplicity.

Chibnall (who's written for "Doctor Who," "Torchwood" and "Law & Order: UK," among others) sets up an elegant conflict between the sweet, optimistic Miller and the damaged, misanthropic Hardy that transcends cliche because each of them feels like a specific person beyond their respective philosophies. Similarly, Danny's parents Beth (Jodie Whittaker) and Mark (Andrew Buchan) aren't just collateral damage, but complicated adults with problems that the tragedy either exacerbates or puts into perspective.

The case proceeds in a linear fashion, with one significant suspect at a time, but unlike "The Killing" (even in its much-improved third season), Chibnall doesn't expect either the cops or his audience to automatically believe this latest suspect must be the killer. People have many reasons for lying to the police, and Hardy and Miller seem to spend as much time trying to prove that someone couldn't have killed Danny as they do finding evidence that they did it.

The no-frills approach at times threatens to make "Broadchurch" seem generic in its early going. I watched the series after several of my colleagues, and when I told them I found it unremarkable after the first few hours, they told me, "Just wait. You'll see it." They were right. Chibnall, Strong and company are doing a very deliberate, gradual build to something here, and the plain approach makes the moments of discovery all the more painful.

"Broadchurch" is a police procedural, and an effective one, but what renders it special is the way it tracks the ways that physical and emotional violence haunts everyone in the town. Several of the citizens, it turns out, moved to Broadchurch to escape a dark past that the investigation unfortunately digs up. Beth Latimer is so consumed with grief that she reaches out to a mother who's been through a similar ordeal, hoping against hope that this woman will say the magic words that will make her pain go away.

The performances are excellent throughout, with the two cops and the two parents deserving every moment spent on them. Tennant has the flashier part, spitting his words out in a thick Scottish burr and seeming on the verge of collapse in every scene. Colman's role is trickier, and ultimately more powerful, because Miller is still naive and innocent when the case begins, and something very different when it ends and she's learned all there is to know about her hometown. Both of them, and Whittaker and Buchan — and David Bradley, known in the States as nasty Walder Frey on "Game of Thrones," and here plays an elderly news vendor — do work that I'd slot comfortably beside the top American performances of the moment.

One of the case's many suspects declares, "Death; once it's got its claws into you, it never lets go." This is a fact that slowly and painfully dawns on the people of Broadchurch, and this is a miniseries that will have you in its grip long after it's done.

Alan Sepinwall may be reached at sepinwall@hitfix.com

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NOTE: Same spoiler rule as usual applies to a foreign import: if it hasn't aired yet in America, it's a spoiler. So for those of you who've seen the whole series, don't give away whodunnit, how, why or anything else. I'll be doing another post when the series concludes in eight weeks so we can all discuss that together.