Edwin Beauclerk is a non-canonical character created for the 2013 ITV adaptation of Greenshaw's Folly. He was the younger brother of Cicely Beauclerk and a former student at St Faith's Orphanage who died long ago in 1900, more than 50 years before the events in the episode. Edwin is only seen in a photograph. Cicely also visits his grave in one scene. Edwin's tombstone indicates that he died on 31 May 1900 at the age of 11.
Edwin, like Cicely, are involved in a major sideplot of the episode involving the relationship between Greenshaw's Folly and St Faith's Orphanage. Between 1900 and 1910, Decimus Greenshaw, the father of Katherine Greenshaw had been conducting experiments in a laboratory in the house. He was involved in "the great race", an effort to develop a vaccine for polio. To that end, he took orphans from the orphanage to experiment on and Edwin was one of his subjects. He was taken away and subsequently died as a result of the experiments. For many years, Cicely had been haunted by this memory and the feeling of guilt that perhaps she should have tried to defend her brother. These memories were stirred up again when Miss Marple asked her if she understood what "the great race" was.
Towards the later part of the episode, Cicely broke into the laboratory at Greenshaw's Folly and found Archie Oxley who had been locked in there. Cicely dragged Archie from the place. She kept calling him "Edwin". In her fantasy she thought he was Edwin and she wanted to try to rescue him from the clutches of Decimus Greenshaw.