Very “X-Files”-ish in tone (and featuring some prominent alums of that show among its producers), “The Intruders” is another moody, macabre drama that proves too stingy about disgorging its secrets. Adapted from Michael Marshall Smith’s novel, the series involves, as the press notes explain, “a secret society devoted to chasing immortality by seeking refuge in the bodies of others,” without really making clear the rules through two rather violent episodes. Fans of the genre might be more patient about where this serialized story is heading, but those confined to one lifetime should think twice before potentially squandering some of it on this.

Set in the Pacific Northwest, this British production has most of its cast adopting Yank accents, presumably for the practical purpose of securing Canadian tax credits. Developed by Glen Morgan (and counting his brother Darin, another “X-Files” veteran, among its producers), the series stars John Simm (the original “Life on Mars”) as Jack Whelan, a former cop turned author whose wife (Mira Sorvino) goes missing, leading him toward this twisted world of the Qui Reverti, who essentially recycle themselves by occupying the forms of others.

“Toward” is the operative word here, since after a couple of episodes, Jack seems not much closer to ascertaining what the hell’s happening, despite a friend (“True Detective’s” Tory Kittles) who points him in the direction of a suspicious dual homicide. That leads to a parallel plot featuring James Frain as an implacable killer, piling up victims as he seeks a little girl (Millie Brown) who has apparently become host to one of the intruders, and represents a threat — for reasons that remain vague — to the rest of them.

Admittedly, other BBC America imports in this vein, among them “Orphan Black,” have also been slow to peel back their mysteries, but at least that offered the pleasure of Tatiana Maslany’s performance to carry through the early going.

“The Intruders,” by contrast, somewhat handcuffs its cast, while concocting an eerie atmosphere of things that go bump — and in Frain’s case, bang-bang-bang — in the night, especially in terms of Brown’s increasingly precocious tyke.

As adapted by Morgan and Eduardo Sanchez (who wrote and directed, respectively, the first four of the eight episodes), “The Intruders” owes a thematic debt to “Invasion of the Body Snatchers.” The show also benefits from “The Walking Dead” composer Bear McCreary’s ominous score, which contributes mightily to conjuring a sense of dread.

None of that, however, provides a strong enough incentive to stick with the show, based on these initial hours. And while there’s clearly an audience for such fare — and BBC America will provide the show with a nice springboard, premiering behind sci-fi staple “Doctor Who” — there’s just not enough life in the concept thus far to prevent “The Intruders,” like its namesake, from hiding in plain sight.