Set In The Summer Of 1917, The Story Follows The War-wounded Hastings To The Styles St. Mary Estate Of His Friend John Cavendish. The Cavendish Household Is Wrought With Tension Due To The Marriage Of John's Widowed Mother To A Suspicious Younger Man. In The Village, Hastings Runs Into His Old Friend Hercule Poirot And, When The Estate's Trouble Turns Deadly, The Friends Unite To Solve A Most Baffling Case.