The Eldritch Feud
Part 1 Scene 7
As the investigators are searching the study, get them to make a listen check.
If they succeed, they hear two men enter the house. If not, they encounter them when they move down stairs or, if they take too long, when they smell smoke. They are dressed in trench coats and packing Tommy-guns and carrying cans of gasoline. They attack the investigators on sight and if the investigators retreat upstairs, they attempt to burn the house. They are careful not to carry any ID, and they have a getaway car waiting outside.