Later this summer I set sail across the Atlantic on the Queen Mary II, the perfect place for a locked room mystery! While much larger than Agatha Christie’s vessel in Death on the Nile, it has a common essential element – no one can come on or off. If you aren’t familiar with the idea of a locked room mystery, here are a few essentials and a confession.
Closed Circle versus Locked Room
The confession is the over use of the term locked room. This is a common term among readers and writers alike, however, it is often used incorrectly. My debut novel Swiss Vendetta is often referred to as a locked room mystery, with the crime taking place at a chateau during an ice storm which sealed all of the suspects in. Technically, this is a closed circle mystery. A key difference is that with a true locked room mystery the solution – any solution – seems impossible.
The birth of a genre
Edgar Allan Poe’s The Murders in the rue Morgue (1841) is acknowledged as the inaugural locked room puzzle. In it, a group of neighbors hear screams emanating from an apartment and rush to lend aid. After battering down the door they discover the bodies of a mother and daughter, both savagely murdered. The door was locked, the windows closed and fastened, the chimney impassible and the floor intact. An impossible crime. When the detective sees the solution – demonstrating his unique brilliance – a genre was born.
The Golden Age of fiction and of the locked room mystery
The period between the two world wars was the Golden Age of detective fiction and for many readers the pinnacle of achievement was the locked room. Agatha Christie excelled at this puzzle, and readers delighted in the ‘who dunnit’ and the ‘how dunnit’ more than the why anyone did anything. Her And Then There Were None remains a gold standard for impossible solutions while The Murder of Roger Ackroyd, with its literal locked room, catapulted her writing career to stardom.
Closed Circle mysteries
The closed circle mystery, including Agatha Christie’s Death on the Nile, where the murder happens on a river barge, is closely related to the locked room, with its closed location (room, isolated house, ship). The key difference is that the crime doesn’t seem technically impossible. In fact, there may be too many possible suspects and conflicting testimony and alibis.
The modern genre
Closed Circle mysteries remain favorites. The Hunting Party by Lucy Foley creates a closed circle when old college friends are snowed in at a hunting lodge. Ruth Ware’s The Woman in Cabin 10 and One by One are two of my favorites (clearly I’m partial to ships and to snowy adventures).