Celebrated sleuth Hercule Poirot, now retired and living in self-imposed exile in Venice, reluctantly attends a Halloween séance at a decaying, haunted palazzo. When one of the guests is murdered, the detective is thrust into a sinister world of shadows and secrets.

Set during the summer of 1957. Ex-racecar driver, Enzo Ferrari, is in crisis. Bankruptcy stalks the company he and his wife, Laura, built from nothing ten years earlier. Their tempestuous marriage struggles with the mourning for one son and the acknowledgement of another.