A rather loose adaptation of the P. D. James novel. Cordelia Gray, the survivor of a partnership in a detective agency, is asked by the assistant of James Calendar to investigate the suicide of his son, Mark. About the same age as Mark, Cordelia is resourceful in her investigation, but smitten with the dead son and becomes obsessed with his memory and his increasingly suspicious death. She interviews his friend, Andrew, and his girlfriend, Isobel. She is also interested in James Calendar's assistant, Elizabeth Leaming, who seems to have a more than natural interest in Mark. She is thrown down an abandoned well and later chases her assailant, Andrew... A London private eye on her first case probes the supposed suicide of a rich young man.