Michael MacCauley: What happens when you find 'em?
Joanna: They die. Hypothetically.
Michael MacCauley: What have you done to my wife and son?
Joanna: What if someone asked you to do one little thing but would affect another passenger on this train? Would you do it?
Michael MacCauley: I don't know. What's in it for me?
Walt: I gotta take a leak. My prostate's bigger than your head.
Joanna: It doesn't have to end this way. Think about Karen, Danny.
Michael MacCauley: Don't you dare mention their names.
Answer: The opening credit scene (waking up, in the kitchen, the drive, being on the train, and walking through the terminal) is montage where each cut represents another day in Michael's life. It's meant to show the monotony of his life through the whole year (or even years) and how he follows the same routine everyday.
Bishop73