Who Are You?

The Machinist opens up with credits while we hear a struggling Trevor Reznik (Christian Bale) trying to roll up something in a carpet, most likely a body. He drives his truck near a dam and does indeed have a body to dispose of. He hurries when someone starts to come closer, holding a flashlight. He pushes the body down, but the carpet starts to unravel, and we assume we will see the body. Just then, the man with the flashlight catches up to him and says, "Who are you?"

Stevie: Are you okay?
Trevor Reznik: Don't I look okay?
Stevie: If you were any thinner, you wouldn't exist.