Take a shot of whatever if:
1. You see a full moon
2. Hear or see a screeching owl
3. Take a shot if:
3a. Someone gets thrown down the stairs
3b. Someone gets thrown out of a window
3c. Someone gets thrown off the ramparts/roof
3d. There is incest involved
4. There SHOULD be at least 3 murders - all committed by the same one or two people.
5. This show has confirmed the fact that Britain has many amazing actors/actresses, but they only hire the same 30 or so for speaking parts, so don't be surprised if you see people you've seen in other shows/movies. In some ways it's comforting; in others, a lazy effort...and you'll find they use the same ones multiple times.
This is just for starters. Methinks you'll get rather sloshed just following these for a while.