A damaged ex-special forces soldier navigating London's criminal underworld seizes an opportunity to assume another man's identity.

Leaving the construction site on the eve of a major project, construction manager Ivan Locke receives news that sends him driving the two hours from Birmingham to London, but even further from the life he once knew. Making the decision that he has to make, he then calls his wife, his sons, his co-workers and boss telling them the secret that he is bearing and trying to keep his job and family intact. But even more importantly, he will have to face himself and the choices he has made.

Baker Dill (Matthew McConaughey) is a fishing boat captain leading tours off a tranquil, tropical enclave called Plymouth Island. His quiet life is shattered, however, when his ex-wife Karen (Anne Hathaway) tracks him down with a desperate plea for help. She begs Dill to save her - and their young son - from her new, violent husband (Jason Clarke) by taking him out to sea on a fishing excursion, only to throw him to the sharks and leave him for dead. Karen's appearance thrusts Dill back into a life he'd tried to forget, and as he struggles between right and wrong, his world is plunged into a new reality that may not be all that it seems.