This fast paced sci fi thriller fortunately does not slow down long enough for most of the audience to start asking awkward questions about the accuracy of the science behind its main premise. Colter Stevens (Jake Gyllenhall) wakes up in an express train carriage opposite a friendly woman,Christina (Michelle Monaghan) who he has never seen before, but who apparently knows him as someone else. His last memory is of a fire fight in Afghanistan and with no idea of how he got aboard this Chicago bound train, he glances in a wash room mirror to discover the face he sees is not his own. The explanation for this when it finally comes from a military scientist,Rutledge (Jeffrey Wright),involves Quantum Physics, and in about thirty seconds,Stevens is told that he is inside the head of a dead man with a task of identifying a terrorist bomber in the same carriage in only eight minutes. To use their jargon he is part of their source code, and he is forced to relive the same eight minutes over again until he tracks down the bomber. So much for Quantum Physics and science, but this is presumably science fiction with a strong emphasis on the fiction.
Actually, I think the science is just an excuse for the film makers to play with alternate reality once again, and on that level it is entertaining enough. For those who argue that the events in it are implausible and stupid, much the same criticism could be said of films like Fellini's Eight and a Half, reality television, and a great deal of everyday life in our real world. Simply put,this is a variation of Ground Hog Day in a more serious context, with time cut to eight minutes, and an explosion at the end of it.
In the ninety minutes of action there is not much room for character development, and Jake Gyllenhall and Michelle Monaghan get to play a range of variations of their behaviour and actions from previous versions of those important eight minutes of those alternate realities. Some have also criticised the ending, but if Stevens has actually defused the bomb,as we see him do,then how else could it end? We might have to delve into Quantum Physics again to find the true answer.
Finally what made the film so personally entertaining for me is when the bomber attempts to activate his nuclear device from a railway car park,at Glenbrook Station near Chicago. As I saw this film with a stony faced audience at Glenbrook Cinema near Sydney Australia, and live next door to the railway car park at Glenbrook Station near Sydney, I will be forced as a result of viewing this film to play closer attention to what goes on there in future.