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In the Miss Marple short story The Idol House of Astarte, Elliot Haydon is a barrister and the cousin of Sir Richard Haydon.

At a house party at Sir Richard's place "Silent Grove" in Dartmoor, Sir Richard was stabbed to death in mysterious circumstances and for a time no one could explain how it had been done and who had done it.

Some five years later, Elliot wrote to Dr Pender, Sir Richard's friend, to confess to the crime. Elliot had seen himself, a mere struggling and poor barrister, as an underdog in the rivalry with Sir Richard for the love of a girl named Diana Ashley. When Sir Richard had tripped and fallen, Elliot had knelt beside him and, with no one else able to see what he was doing, Elliot had, at that time, been dressed as a brigand for the house party fancy dress event and so had a dagger with him. The dagger jerked out as he knelt and, almost without thinking, Elliot drove the knife in. He later stabbed himself to divert suspicion.

Elliot thought that with Sir Richard dead, he would at least inherit his cousin's title and money. In the event, he did not profit from his act--he told Dr Pender he had lived five years of hell since the murder. In the end he joined an expedition to the South Pole where he managed to do what he had hoped to do, expiate for his crime by dying honorably.