“Mr. Prichard, the people you see in the photos will be killed within the next forty-eight hours, unless you stop me. I have been following your exploits closely, and I think that you are the one I need to make sure I stop doing this. I've been trying for more than fifteen years to kick this habit, but I can't.
Normally, I don't strike so many times so close together, but in order to get you interested, I'm going to up the odds. I need you to do only two things: discover who each of my victims is, and then do all you can to stop me before I can kill each one.
The first one will die exactly twenty-four hours after you receive this note.
The second will die twelve hours after that...
...and the third twelve hours after that.
If you cannot stop me before I can kill the third one, then no one can. Then there will be a fourth victim, but you get no clues for that one. Good luck."