As Cube opens, a handful of people find one another after each has been placed into a mysterious complex of square rooms. Each room is joined on each of its six sides to another, identical-looking room, some of which have been booby-trapped, some of which are safe, and all of which seem to lead nowhere, offering no explanation. For his first feature, Canadian director Vincenzo Natali has, like the setting of his film, created a complex piece of work around an essentially simple foundation. As each of Cube's characters unravel the mysteries of the cube, or seem to, they unveil aspects of their personalities, secrets from their past, and hidden talents and motives. Natali and co-writers Andre Bijelic and Graeme Manson do a beautiful job keeping things interesting, concealing as much as they reveal, turning viewer loyalties on their head, and moving things along in a movie that, in the literal sense, goes almost nowhere. Cube does stall in the moments when it threatens to reveal itself as the rather simplistic political allegory that at heart it probably is, but those moments are rare. The film's strength lies in maintaining its ambiguity, which is occasionally short-circuited by some cast members' overly broad characterizations. But those flaws never prevent Cube from remaining interesting, nor do they keep it from being at least as provocative as [Pi], last year's other, higher-profile cerebral mathematical thriller.