Half-Life 2

You are Gordon Freeman, one of the lucky few employees to escape from The Black Mesa Research Facility after "The Incident". The game starts with you being told by the G-Man that you've been sleeping on the job, but you don't even know what job that is. Then you appear on a train bound for City 17, with one of the passengers telling you that he didn't see you get on. City 17 is a horrible place ran by The Combine and Dr Breen. Why are you here? What do you do? You, once again, have to find out.