Isabelle, a young museum curator played by Katie Goldfinch, is tasked with examining an ancient artifact found in the basement of a grand estate in Shropshire. Upon her arrival, she is greeted by a family that appears warm and welcoming: Karl (Larry Rew), his wife Evelyn (Babette Barat), and their stunning daughter Scarlet (Florence Cady). However, beneath the surface of this seemingly gracious household lies a sinister and frightening secret.