This is a well produced movie with some stunning action sequences. The problem is that it is horribly confusing with the viewer trying to follow a forward moving timeline travelling in reverse. As a physicist I was looking forward to a challenging watch and boy did I get it! The concept is easy enough to grasp but the delivery might leave many scratching their heads. It is a marathon at 2.5 hours and though you don't notice the length so much there is a significant amount of neural fatigue by the end. It definitely needs more than one watch but I don't think I have the stamina. Great if you like mind benders like matrix but it's hard work entertainment wise.