An original and well directed thriller but very unemotional and superficial. It's more like you're watching a videogame instead of a film, the soundtrack was pretty lousy too and the acting below par.
For better movies on this theme (coincidences; movies that handle one situation from different angles), try La Via Lactea (superb Brazilian film), Smoking-no Smoking by Alain Resnais or Akira Kurosawa's Rashômon. I rate all those higher than this one.