"Simple. Get a back room here of your choice, or better yet, an open square outside. I'll get across or into it without being seen. Similar tests can apply for the rest. For example, I'll get into a locked room, with you in it, and steal something out of it. Killing someone is the only thing that presents a difficulty - and that can be done with a dummy, or simply by getting into a position where I could kill someone if I chose"