Source Code - HD Trailer #2

Colter Stevens an American Army helicopter pilot whose last memory is flying in Afghanistan, wakes up on a commuter train. But he discovers he has assumed the identity of another man. 8 minutes later the train explodes and Stevens finds himself in some kind of pod. He then talks to someone named Goodwin who tells him he has to go back and find who the bomber is. He is sent back and is going through the whole thing again and tries to find who the bomber is but fails and the bomb goes off and he is back in the pod. He is sent back again and still can't find out anything. When he comes back he asks what is going on, Goodwin and Rutledge, the scientist in charge tells him he is part of a project that can put someone in another person's consciousness during the last 8 minutes of their life. Stevens says why doesn't he just stop the bomb, he is then told that he is not going back in time but placed in the moment so he can find out who the bomber is and if there are any other targets