The Vault by Murray Leinster

Mike's whole body was bathed in sweat at the thought of himself thrown inside the vault with armor-plated doors inexorably shutting out every atom of fresh air. He clenched his teeth to keep them from chattering. The man outside took on the aspect of a monster. To Mike, he was something more or less than human. Mike might be a criminal, and could visualize,–shrinking,–the thought of killing a man in making a getaway, but not the deliberate strangling of a man in cold blood, for the covering of his tracks. That was the other man's plan.

There would have to be a struggle, a fight of some sort. Mike's leg throbbed horribly. He doubted that it would support his weight. And in an instant or two more he would inevitably be fighting. One way or another, he was bound to be in terrible danger. If he shot the other man, the pistol-shot would raise an alarm. If he did not shoot.