Thanks to the Recommend some “puzzle” fiction thread, I’ve been listening to the excellent BBC audiobook version of John Dickson Carr’s “locked room” mystery The Hollow Man (known as The Three Coffins in the US). I enjoyed it very much, but there are a couple of aspects of the rather complex plot that I don’t understand:
Spoiler alert - if you like mystery stories and haven’t read this one yet, read no further!
[ul][li]How did Grimaud leave his study (to go and kill his brother) without his secretary Stewart Mills seeing him? Mills said that he had had a clear view of the study door all evening, and nobody came out.[/li][li]The sleuth Gideon Fell surmised that Grimaud did not enter his brother’s apartment through the main entrance, for fear of being seen. He went via a nearby apartment and then up on to the roof. So how come his brother didn’t think it odd that Grimaud came in through the skylight rather than knocking on the door like a normal person?[/li][li]Returning to his house, Grimaud sneaks into his lodger’s room while the lodger is asleep and steals a firework, because he needs to simulate a gunshot. Why did he leave this to the last minute? He was never going to have the gun with him, so why didn’t he buy a firework in advance?[/li][/ul]
Can anybody who’s read this book enlighten me?