The Book is an Investigation in Arkham Detective Tales by Pelgrane Press. I ran it yesterday for a group of 4 players, 2 of which had played Trail before, 1 that had played Call of Cthulhu before and 1 that had read the Trail book. I started to run out of time, so I kind of rushed the ending, but I felt that the players were also getting anxious to get to the really scary stuff. We all had fun and I would definitely run the adventure again.
In the adventure, a group of investigators follow the trail of a possible serial killer. The investigators go from killing to killing and then start tracking down the provenance and copies of The Book from the title of the scenario. The ending is suitably horrible with every potential for a TPK. However, the actual deaths of the investigators coming after the scenario is over, that being the best of all worlds. Things are horrible and your character is going to die, but you, the player, still get to see and participate in all of the story.
Let me go into a little bit of how I prepared for the game. Usually when I am preparing one of the Trail scenarios, I find there is a bit that feels awkward to me. In this scenario, that part was the introduction of the private investigator Francis Moon. So the first thing I did was figure out how to use that character. The scenario suggests having him stick around with the investigators. I did not like that idea, Having a NPC hang around the PCs is the fastest way to make them suspicious of the character. So I needed another way to include him. I had him show up at the end of the second killing scene and then he lurked around in the background of nearly every other scenes.
The other problem I saw was how to get the PCs to read The Book. So I decided to make it real easy to suffer the ‘infection’ of the book. Merely flipping through it caused the base level of infection, and things just got worse from there. Next, I mapped out all of the scenes as blocks in a flow chart. This made it easy to see what scene might come next. As I ran the game, I also kept records on how long it took to complete the scene. Another thing I have been doing is put the enemies on a 3×5 card with all of their relevant stats, this makes it easy to run the inevitable combat. Finally, I made a list of the NPCs with a one line on who or what they were. This was very useful and I will do that for all of the Investigations in the future.