Here's the scenario. It's 5 a.m. and you've stopped in at your favorite gas station for a cup of joe. The place is empty except for the clerk who is a small elderly lady. After you pour your coffee you turn around to go pay and see a large, menacing looking dude pulling a handgun out of his jacket pocket. He obviously didn't notice you when he came in and, somehow, you didn't hear him come in, either. With his back to you, he points the gun at the clerk, tells her to empty the drawer and threatens to shoot her. What's your next move?