Sophie Hannah is the New York Times bestselling author of numerous psychological thrillers, which have been published in 51 countries and adapted for television, as well as The Monogram Murders, the first Hercule Poirot novel authorized by the estate of Agatha Christie, and its sequels Closed Casket, The Mystery of Three Quarters, The Killings at Kingfisher Hill, and Hercule Poirot's Silent Night. Sophie is also the author of a self-help book, How to Hold a Grudge, and hosts the podcast of the same name. She lives in Cambridge, UK.