That’s not to say it isn’t creepy, thanks in part to its origins. The film is based loosely on a non-fiction 1975 book by John A. Keel, who investigated a series of bizarre incidents in Point Pleasant, W.Va., in the 1960s. The strangest involved a creature later dubbed the “mothman,” whom witnesses described as a bird-like being that moved like a large human, but had glowing red eyes and enormous wings.

There were dozens of sightings in the area over the course of about two years, and some people claimed that the encounters were accompanied by premonitions of impending catastrophes.

When the nearby Silver Bridge collapsed in 1967, killing 46 people, many immediately connected the disaster to the recent strange phenomena, which diminished soon after. To this day, no one has satisfactorily explained all the events that took place during this period.

The film version of the story takes considerable liberties, fictionalizing virtually everything and setting it in the present day. Washington Post reporter John Klein (Richard Gere) finds himself mysteriously drawn to Point Pleasant after the death of his wife, Mary (Debra Messing), who saw something terrifying just before the car crash that landed her in the hospital. Her drawings of her vision match similar sketches made by Point Pleasant residents, who have been complaining of persistent strange occurrences. John teams up with local cop Connie Parker (Laura Linney) to investigate, and discovers that whatever this creature is, it knows all about him and may have some connection to Mary’s death.

Screenwriter Richard Hatem does a decent job of weaving the recorded incidents into the story, including references to the screeching noises that routinely emitted from radios and phone lines, and creating a character (played by Alan Bates) based on Keel himself, who expounds on some of the author’s more interesting theories about the paranormal.

The problem occurs when Hatem and director Mark Pellington (“Arlington Road”) try to personalize things, making John a specific target of the mothman’s activities. At that point, the movie goes completely haywire, bringing in calls from beyond the grave and other “I see dead people” silliness that has little to do with the rest of the film. This isn’t twisting the plot – it’s mangling it.

Pellington at least has some nice stylistic touches, drawing on his experience at MTV, where he directed promos and worked with bands like Pearl Jam (he did the disturbing “Jeremy” video). Almost everything in the movie seems ominous, from the voices on a tape recorder to the way the lamps cast shadows in John’s motel room. It’s enough to build up atmosphere, at least, and provides a jolt of energy to counter Gere’s bland performance (his one big emotional scene could have come from another film altogether, and is actually kind of embarrassing).

“The Mothman Prophecies” has been compared to “The X-Files,” and it shares much in common with the long-running TV series. Both are set in gray, doom-laden landscapes, take themselves completely seriously and use real accounts of the supernatural as inspiration. They are also both at their best when they stick to the basic story, instead of veering off into complicated mythologies that make less sense the more they’re “explained.”

By the time it’s over, “The Mothman Prophecies” has replaced its eerie atmosphere with incoherence. The only thing scary about that is what it does to an otherwise promising film.