A pet peeve of mine: I keep seeing detective/mystery books advertised as "locked room mysteries" when they are nothing of the sort. What they mean is "closed circle of suspects".
A locked room murder mystery is an impossible crime. The murder has happened in a room locked from the inside or in some other location that no murderer could possibly access and/or leave. The mystery is not just who committed the murder, but how it was physically committed. Classic examples are The Murders in the Rue Morgue by Edgar Allan Poe, The Mystery of the Yellow Room by Gaston Leroux, or The Hollow Man by John Dickson Carr.
Closed circle of suspects is a mystery where we know that the murderer must be one of a small, defined group of people. Typically, only people from that group had the opportunity to commit the crime. Alternatively, it could also be that only people from that group had the motive. The former has the advantage that the motive might not be known, making it part of the mystery. Most mysteries from the Golden Age of Detective Fiction (Agatha Christie, Dorothy L. Sayers, John Dickson Carr, Ngaio Marsh, Margery Allingham, Ellery Queen…) are like this.
A mystery story could be both, but locked room mysteries are much more unusual. Most mysteries with a closed circle of suspects are not locked room mysteries.
Another classic type of mystery story is the inverted mystery. In those, the author tells the reader from the beginning who the murderer is, and how they did it, and why. Then the mystery becomes: how will the detective catch the killer? A classic example is Malice Aforethought by Francis Iles. Each episode of the Columbo TV show was also an inverted mystery.
by farseer6
2 Comments
Benoit Blanc explains this pretty well in Wake Up Dead Man
It always makes me laugh that the solution to one of the first murder mystery storylines was basically “a big monkey did it”.