Martin Dering

In the novel The Sittaford Mystery, Martin Dering is and author and the husband of Sylvia, the niece of Captain Trevelyan. The Derings live in Wimbledon, London, at a house named "The Nook" on Surrey Road.

As Sylvia is one of the beneficiaries of her uncle's will and knew the terms, Martin who is generally thought to be a gambler and a spendthrift became a natural suspect after Captain Trevelyan is found murdered. However, for the time in question, Martin claimed that he spent the evening at a literary dinner at the Hotel Cecil. As for the afternoon, he had lunched with his American publisher Edgar Rosenkraun and was with him all afternoon.

Dering's alibi for the night was however broken by a journalist Carruthers who was at the dinner and according to the seating plan was supposed to be next to Dering. He reported that Dering never showed up. As for Rosenkraun, when, on Dering's request, Inspector Narracott telegraphed him in his personal name without mentioning his police position, the American publisher did reply that Dering had been with him in the afternoon. However, Narracott, being a suspicious man, sent another telegram in his official capacity. This time Rosenkraun replied that Dering was not with him. Rosenkraun had agreed to lie for Dering as a favour from one friend to another because he believed Sylvia was having Martin watched in preparation for divorce proceedings. Dering declined to reveal who he was with in the evening, although Narracott could guess.

While at Dering's house, Narracott discovered a book Pride and Prejudice with the name "Martha Rycroft" on the flyleaf. A check with Somerset House revealed a marriage record for William Martin Dering (Martin Dering's father) and Martha Elizabeth Rycroft in 1894. Martin Dering is therefore the nephew of Mr Rycroft of No. 3 cottage at Sittaford, drawing in yet another person as an interested party in the death of Captain Trevelyan.

Martin Dering is described as a man  of  middle  height  with  thick  rather  heavy chestnut  hair. Narracott observed that he was good-looking  "in  a  somewhat  heavy  fashion, with  lips  that  were  rather  full  and  red." His relatives describe him as a "moderately successful author". Carruthers calls him "that sex specialist". Emily Trefusis dislikes him. She thinks of him as an ideal person for a murderer--he is always getting telegrams from bookmakers and losing money on horses.