Like the current, seemingly never ending presidential campaign season, James Wan’s Saw starts off incomprehensibly, turns nasty in a hurry, and ultimately induces numb exhaustion. This serial-killer potboiler chains two ostensibly unrelated mooks (Cary Elwes and co-screenwriter Leigh Whannell) in a makeshift dungeon, where several strategic clues have been planted to reveal the grisly fate their unseen captor has in store for them. A disturbed ex-cop (Danny Glover) hovers as one of the movie’s many red herrings. While Saw makes good use of its minimalist plotting, it cries out for understatement: First-timer Wan has an aptitude for building tension, but he proves too reliant on grating, heavy-metal-video stylistics and expository flashbacks to maintain focus. He also seems incapable of (or uninterested in) motivating his cast—this could be Glover’s worst ever performance. Nevertheless, with its toilet-bobbing and blood spurting and Elwes’s fey, Vincent Price–like mugging, Saw succeeds in capturing something like Takashi Miike by way of William Castle. Happy Halloween, indeed.