UNCOMMON MYSTERIES: Anthony Berkeley [Anthony Berkeley Cox], The Poisoned Chocolates Case (1929)

           In “The Avenging Chance,” a short story published earlier in 1929, novelist and amateur detective Roger Sheringham finds a murderer for his friend Chief Inspector Moresby. A man sends poisoned chocolates to a friend, then induces the friend to give him the chocolates. He cleverly eats several himself, becoming sick but not dying, having already given them to his wife, who does die. The novel adds the fiction of the Crimes Club, a fictional model of The Detection Club that Berkeley had founded the year before with Christie and others. The same facts about the murder are presented by Moresby to the six members of the club, and then Sheringham challenges everyone to solve the crime. They come to six different conclusions, pointing out the arbitrariness of the usual mystery solution, where any one of a closed circle of suspects could have committed the crime. One of the club members accuses another member of the crime, another accuses himself, adding that he could as easily pin it on the Archbishop of Canterbury, or the President of the United States. Sheringham’s solution, the same as that of the short story, is demolished by the next presenter, a brilliant woman novelist who turns out to be the murderer. The last presenter produces a chart, the mainstay of so many classical mystery stories, but this chart, instead of being helpful, shows that each of the known facts Moresby related was used for half a different deductions by the members of the club.