“It’s just the wind,” goes the attempt at reassurance in your average haunted-house story. In Below, a clever horror flick set aboard a World War II submarine, the men tell each other, “It’s just the water.” Ably directed by genre specialist David Twohy (Pitch Black), Below combines the paranoid claustrophobia of a submarine movie with the unsettling spookiness of the supernatural. It’s a potent formula for fear.
