Mary Durrant (Double Sin)

In the short story Double Sin, Mary Durrant was a nineteen year old girl who helped her aunt Elizabeth Penn run an antique shop in the town of Ebermouth in Devon.

Mary met Poirot and Hastings during a bus tour to Charlock Bay from Ebermouth. She told them that she had come to live with her aunt to learn the business and much preferred it the other alternative of becoming a nursery governess or companion.

Throughout the trip, she appeared "ingenuous as a child", confiding in Poirot and Hastings that she was carrying a set of valuable miniatures to a customer at Charlock Bay and that she would be carrying a large sum of money on the return trip.

It later turned out that this was a front. She had been conspiring with her aunt to defraud an American tourist J. Baker Wood who had been interested in buying a set of miniatures. Poirot found her naivete and openness with two supposed strangers suspicious. As Poirot put it, Mary had hope "a couple of mugs who will be sympathetic to her charm and champion beauty in distress." Unfortunately for her, one of the mugs was a no-mug but Hercule Poirot.

Christie actually uses two characters with this same name but in works separated by almost thirty years so she might have forgotten.

Portrayals
Mary Durrant was played by Caroline Milmoe in the film adaptation of Double Sin in Series 3 of ITV's Agatha Christie's Poirot drama series.