This one was kind of a let down. Much of the film is appropriately grim and vile. The murder and rape scene is disturbing and horrific. And while Craven does a commendable job of racheting up the tension, the shifts in tone(wacky, bumbling cops?!) do not work at all and undermine the movie as whole. It really takes you out of the film, making it all too easy to remind yourself that "it's only a movie."
Still, David Hess turns in a career making performance as one of the screen's most heinous psychopaths and the creepy folk music that he contributed to help score the film is pretty brilliant.
The film which is a variation on Bergman's Virgin Spring, has been ripped off a dozen times. In fact, this story was told much more successfully, IMO, in the Italian film Night Train Murders.