Frances Jellico is dying. A man who calls himself the vicar visits, hoping to extract a deathbed confession. He wants to know what really happened that fateful summer of 1969, when Frances – tasked with surveying a dilapidated country house – first set eyes on the glamorous bohemian couple, Cara and Peter. She recalls the relationship they forged through sweltering days, lavish dinners and elaborate lies, and the Judas hole through which she would spy on the couple.