Behind that dial is a bunch of mechanical stuff that has gotten Waterhouse completely pissed off, driven him into a frantic state. By manipulating this dial in some way, he should be able to tease that mechanical stuff into some configuration that allows the door to be opened. That’s all there is to it. That this door remains locked is an outrage. Why should the tiny volume inside this safe—much less than a single cubic foot—be so different from the space that Waterhouse moves through at will? What the hell is inside there?