Apparently Christian Bale did some serious method acting for this, and with commitment like that it deserves a watch.
Trevor is a machinist and hasn't slept for a year this is also effecting his health to the point where he looks anorexic, he seems to be well liked amongst his colleagues until an accident involving a machine causes a work mate to lose his arm, he blames a workmate named Ivan for distracting him, however when an investigation is launched it appears that there no-one at the factory called Ivan.
Trevor regularly visits a prostitute who seems to have genuine emotion for him and doesn't see him as a way to make money, as she offers to make him a meal he however refuses and leaves his money and goes after leaving Stevie (the prostitute) he spends his sleepless nights at an airport waiting lounge where he also struck up a friendly relationship with the waitress there, Maria (the waitress) asks him to join her for a day out with her son which he happily accepts, he goes out on the Sunday with Maria and whilst going on a ride with her son starts seeing some disturbing imagery, however whilst on the ride Nicholas has an epileptic seizure, he takes Maria and Nicholas home and accompanies them into the house but then leaves after he starts seeing a note on her fridge similar to the ones that have been left on his, he later goes back to Stevie who tells him that she would give prostitution for him as she thinks he is Mr.Right.
Trevor is growing increasingly paranoid after spotting Ivan, he follows him to a pub where he takes a picture of Ivan with one of his co-workers and seems to come to point where he thinks there is a conspiracy against him, after another accident at work he confronts the co-worker who he suspects has the vendetta against him and is immediately fired, He is growing increasingly distracted and even more paranoid and goes to the house of workmate who's arm got chopped off and accuses him of trying to drive him mad with the messages on his fridge, he tells him to leave and attacks him, whilst getting into his car he see's Ivan again and tracks his number plate.
He goes to the DMV and tries to get the address they refuse and they tell him the only reason he would get that information is if a crime is committed and because he is that committed to get the information he throws himself in front of a car and then goes to a police station to report a hit and run, however the police come back to him and tell him that the number plate supplied to them is registered to Trevor and he reported it wrecked in a accident a year ago, the police accuse him of filling a false report and he runs from the police and goes to Stevie, whilst there he see's the picture he took from Ivan at the pub and accuses her sleeping with Ivan and that she has been keeping things from him, she tells him all she see's in the picture is Trevor and a co-worker not of anyone called Ivan, she throws him out after he becomes abusive, he then goes to the airport to see Maria but she is not there but is greeted by another waitress who informs him that she is the one who has waited on him for a year and they have never spoken.
I am going to stop it there as we are at the finale of the movie and there is quite a few surprises that shore up the film, I really wanted to like this film and as well acted as it is, its overly complicated and quite tricky to follow don't get me wrong I don't dislike it but I just didn't get it, However a special mention goes out to Christian Bale who lost more than 60lbs for this role, now that's dedication !!.