The character of the landlady was so well executed and I could visualize how eerie and strange the environment was. I also solved the puzzle pretty quickly as most readers would but billy did not because he is not educated and has no critical thinking skills whatsoever. Personally, I would not have drank a cup of tea from a stranger I just met who is begging me to drink it frantically, and trying to cover up the fact that these two men that have stayed here went missing. And it smelled of arsenic so there's another thing. My main annoyance is Billy's lack of common sense, although it basically is crucial to the plot. 8/10 good story