[Bruce purses his lips, impressed, but he's being calm about it. The leaving in a hurry and the timeline of when they left he could guess, at least.]

Are you a detective? What're you thinking caused them to hurry? It didn't seem like there was any kind of forced entry...

[He isn't thinking a murderer, because whatever booted them is likely to have booted the rest of the town. He's thinking, as he so often does, military, or at least mass evacuations.]

I wonder if there's some kind of plant or laboratory nearby...