Tyler Durden: [pointing at an emergency instruction manual on a plane] You know why they put oxygen masks on planes? Narrator: So you can breath. Tyler Durden: Oxygen gets you high. In a catastrophic emergency, you're taking giant panicked breaths. Suddenly you become euphoric, docile. You accept your fate. It's all right here. Emergency water landing - 600 miles an hour. Blank faces, calm as Hindu cows. Narrator: That's, um... That's an interesting theory.