...There's precedent. That other people can arrive from a single world.

[He hesitates. He didn't want to make her worry, but now that she knew this much, she had to know the rest. If only to know how to stay away from them.]

The Organization thinks I'm dead. If one of them arrives here and discovers I am not, they will most likely attempt to fix that. And then they will attempt to kill everyone connected to me.