This shockingly graphic horror film, about the exploits of two American college students partying their way through Europe with an Icelandic guy they've befriended, starts out as a garden-variety sex-and-drugs comedy before taking a decidedly dark turn. After smoking mass quantities of weed and whoring around Amsterdam's red-light district, the three men encounter a Russian who urges them to head for Bratislava, where the women are gorgeous and the men inexplicably few. Director Eli Roth (Cabin Fever) is adept at building a sense of foreboding; unfortunately, once the bloodletting begins, all sense of drama and logic oozes out as well. With Jay Hernandez, Derek Richardson, and Eythor Gudjonsson. R, 95 min.