It's a modest visually treat, and it contains a number of effective and surprising set-pieces. The problem is, they're surprising because no character but the lead has any coherent motivation. Amazingly, they are somehow also remarkably one-dimensional; a great deal seems to happen Because Movie. The interesting premise is given short shrift both scientifically and especially thematically, leaving the first half of the film to be consumed by what should have been a subsidiary plot point. The score distractingly says "creepy" when the visuals say "mysterious," and key elements of the plot puzzle are poorly communicated (it's really not a good idea to signal a character's nature by echoing their speech so severely that it's hard to understand). It was shot in a single abandoned location, a very good thing considering the enormous quantity of scenery chewed. For all its flaws, though, its evident ambition and technical skill make it marginally watchable for sci-fi fans. Horror buffs may fare a bit better.