A dark, empty theater, popcorn, hushed silence – the perfect atmosphere for a scary movie. Instead, however, I got “Swimfan.”

The plot line is simple – at times, painfully so. Jesse Bradford plays Ben Cronin, a high school senior who has everything going for him, including a steady girlfriend named Amy (Shiri Appleby of “Roswell” fame). Enter Madison Bell (Erika Christensen), the new girl in town who has looks, sophistication (she, like all sophisticated people, plays the cello), and a crush on Cronin. Bell throws herself at Cronin and he does what any guy in a good relationship would do: He has sex with her in the pool. Big mistake.

Bell becomes obsessed and everything begins to fall apart, especially the movie itself. I’m easily spooked, but director John Polson shoots the most suspenseful scenes as if he is trying to avoid frightening anyone, making “Swimfan” seem more like a bad romance than a thriller. Yet even the romance is weakly developed, with Appleby’s primary job being to call attention to her eyes, either wide in love or teary in heartbreak, which in turn places a strain on Bradford’s acting. He has much better chemistry with Christensen, showing sexual tension even as he is determined to expose her for the dangerous stalker she has become.

The characters are all woefully underdeveloped and this sinks the film. Christensen does a good job with what little she has to work with, but Bell remains essentially one-dimensional. For example, the audience never learns the reason behind her insanity, and what we do learn about her is confusing. She says she has a boy waiting for her in New York, but then the film mentions her Southern heritage and accent – and Christensen doesn’t even attempt an accent. Then there’s Cronin, whose dark past is alluded to so briefly that it’s hard to understand why the other characters remember it at all. He also remains far too calm as his life unravels, which is unfortunate, considering his best moments come in those few scenes when he does show emotion.

All in all, “Swimfan” is unoriginal and perhaps better suited for a slightly younger crowd that still believes high school romances really will last forever.

You could do worse for entertainment, but my advice is, if you really want to see this movie, to wait until it moves to the $3 screen – where the theaters are always dark and empty.