HEX. Tomorrow, 10 p.m., BBC America.

"Hex" premieres tomorrow night at 10 on BBC America, and its influences are obvious. With its sometimes glib and arch dialogue, and the way it juxtaposes humor, sexuality and genuine scares, "Hex" plays with the same basic and tricky template established by Joss Whedon on "Buffy the Vampire Slayer" and "Angel."

"Hex" writer Julian Jones also borrows from genre classics for his primary story line. There’s an echo of "Carrie" (tormented wallflower develops telekinetic and pyrokinetic powers), "Rosemary’s Baby" (devilish figure seeks earthly vessel for his demon spawn) and any number of films involving voodoo, witchcraft, past lives and possession.

Even with all these TV and movie touchstones, though, "Hex" feels fresh.

If BBC America doesn’t trim all the boldness out of subsequent episodes, "Hex" is likely to delight some viewers and surprise or even offend others. There are some very sexy scenes on the horizon - some in a stylish dream world, others in the actual corridors, bedrooms and bathrooms of the impressively creepy, ultragothic Mendenham Hall boarding school.

The central figure of "Hex" is Cassie Hughes, played by Christina Cole, who is more than up to all the shades her role requires. When we meet her, Cassie is happy to orbit outside the popular-kids circle at her boarding school, concentrating on her art and literature classes and hanging out with her roommate, an outspoken, slightly punkish lesbian named Thelma (Jemima Rooper).

Before long, though, Cassie finds an artifact in a forgotten room in Mendenham Hall and begins to experience visions, then sounds, and finally full-out visitations from a fallen angel named Azazeal. This demon, it turns out, has seduced and tormented select women, including Cassie’s institutionalized mother, over the centuries and now sets his sights on innocent young Cassie.

Tonight’s two-hour pilot establishes the premise and claims a victim from among Cassie’s circle of boarding-school friends and enemies (a list that includes Joseph Morgan as hunky Troy, Jamie Davis as cocky Leon and Amber Sainsbury as vampy Roxanne). The death is unexpected, but even more so is that the victim continues to appear on the series - as a ghost.

And not just to appear, but to delight in such newly endowed spectral powers as entering and influencing the dreams of others, alternately comically and erotically. Meanwhile, Azazeal is manipulating things, too, and eventually uses Troy as a pawn to affect and possess Cassie. And once, midway through this first series run, Cassie joins the dark side, all hell breaks loose. Well, part of it, anyway, in a way that the recent "Point Pleasant" series never came close to achieving.