The Killing of a Sacred Deer is a 2017 psychological horror film directed by Yorgos Lanthimos, from a screenplay by Lanthimos and Efthymis Filippou. The story is based on the ancient Greek play Iphigenia at Aulis by Euripides. The film follows a cardiac surgeon (played by Farrell) who secretly befriends a teenage boy. He introduces the boy to his family, which then falls mysteriously ill.It stars Colin Farrell, Nicole Kidman, Barry Keoghan, Raffey Cassidy, Sunny Suljic, Alicia Silverstone, and Bill Camp. The Killing of a Sacred Deer was selected to compete for the Palme d’Or in the main competition section at the 2017 Cannes Film Festival. It has received positive reviews, and grossed $4.1 million worldwide so far.