To initiate the puzzle, the player must have the Old Notebook and examine the Bloody message on the wall in the Attic. This will add the first set of 5 lines to the notebook. To progress, the player needs to examine the Dummy's Left Hand and make it point to specific locations (that each new line of text Old Notebook describes), which will add a new of bloodstains on the door in the attic, then do a specific action to trigger more lines to appear.
After the last location has been pointed to, the door in the attic will unlock where the player can enter and acquire the Dirty Coin, which in turn unlocks it in the full release of Resident Evil 7: Biohazard.
The door in the attic once all murders have been found