Director: James Wan, 2004
Pros: terrifying, psychologically gripping, not especially gory
Adam (Leigh Whannell) and Dr. Lawrence Gordon (Cary Elwes) wake up in an old bathroom, chained to opposite walls. There's a dead man in the centre of the room, a gun in one hand, a tape recorder in the other. In their pockets they find cassette tapes with messages from the man who put them in the room.
The film alternates between the situation in the bathroom and flashbacks as the two try to understand what's going on.
Like all the best horror films, each scene brings more information, with fascinating twists and turns. And of course, you'll never see the ending coming.
It's gory but not overly so. More is left to the watcher's imagination than shown on screen. The film really uses suspense and anticipation to provide its chills.
I'd put this up there with Jaws, Halloween and Cube.