By the Gods, there's a psychopath on the loose!

I cast Fireball on the DM.

Nono, see it's a "reverse whodunnit," the mystery isn't in who the killer is, we're invested in seeing HOW the killer will get caught!

Remember, your goal as the DM is to make sure no one makes it out alive!

Not the campaign I'm currently playing, nor any of campaigns in recent memory.