world." In 2013, the Christie family supported the release of a new Poirot story, The Monogram Murders, written by British author Sophie Hannah. Hannah later published three more Poirot mysteries, Closed Casket in 2016, The Mystery of Three Quarters in 2018., and The Killings at Kingfisher Hill in 2020. Formula and plot devices Christie has been called the "Duchess of Death", the "Mistress of Mystery", and the "Queen of Crime". Early in her career, a reporter noted that "her plots are possible, logical, and always new." According to Hannah, "At the start of each novel, she shows us an apparently impossible situation and we go mad wondering 'How can this be happening?' Then, slowly, she reveals how the impossible is not only possible but the only thing that could have happened." She developed her storytelling techniques during what has been called the "Golden Age" of detective fiction. Author Dilys Winn called Christie "the doyenne of Coziness", a sub-genre which "featured a small village setting, a hero with faintly aristocratic family connections, a plethora of red herrings and a tendency to commit homicide with sterling silver letter openers and poisons imported from Paraguay". At the end, in a Christie hallmark, the detective usually gathers the surviving suspects into one room, explains the course of their deductive reasoning, and reveals the guilty party; there are exceptions where it is left to the guilty party to explain all (such as And Then There Were None and Endless Night). Christie did not limit herself to quaint English villagesthe action might take place on a small island (And Then There Were None), an aeroplane (Death in the Clouds), a train (Murder on the Orient Express), a steamship (Death on the Nile), a smart London flat (Cards on the Table), a resort in the West Indies (A Caribbean Mystery), or an archaeological dig (Murder in Mesopotamia)but the circle of potential suspects is usually closed and intimate: family members, friends, servants, business associates, fellow travellers. Stereotyped characters abound (the , the stolid policeman, the devoted servant, the dull colonel), but these may be subverted to stymie the reader; impersonations and secret alliances are always possible. There is always a motivemost often, money: "There are very few killers in Christie who enjoy murder for its own sake." Professor of Pharmacology Michael C. Gerald noted that "in over half her novels, one or more victims are poisoned, albeit not