**½/****
starring Kristen Stewart, Vincent Cassel, Jessica Henwyck, T.J. Miller
screenplay by Brian Duffield and Adam Cozad
directed by William Eubank
by Walter Chaw Wasting absolutely no time and not interested in talking to you about it, William Eubank's Underwater is both a model of efficiency and a prototypical post-modernist piece wholly reliant on your familiarity with this genre for its depth and backstory. A seasoned viewer knows that this film is going to be about a small group of survivors picked off one-by-one; that the real bad guy will be corporate greed (or Russian greed, depending); and that if you're African-American or, God forbid, Asian, you'll very likely be the first to go. Curiously, it's in these aquatic thrillers that key exceptions to that rule--Ice Cube in Anaconda, for instance, or LL Cool J in Deep Blue Sea--seem to make their appearance. Maybe the trick to surviving the monster is being a late-'80s rapper. Alas, Mamoudou Athie is not a late-'80s rapper. He plays Rodrigo, friend of plucky engineer Norah (Kristen Stewart), and it's at his urging that Norah saves their deep-sea drilling platform to initially survive a mysterious event--and then through his noble sacrifice that Norah gets to continue to be heroic. It's worth dwelling on this conceit, but there's no time: once the dust settles on the disaster that opens the film, several other disasters follow in rapid succession.