Juliet Forrest, the daughter of noted scientist and cheesemaker John Hay Forrest, asks private investigator Rigby Reardon to investigate her father's death, which she believes to have been murder. Searching Dr. Forrest's lab Rigby finds two lists, one titled "Friends of Carlotta" (FOC) and the other "Enemies of Carlotta" (EOC), as well as an affectionately autographed photo of singer Kitty Collins, whose name appears on one of the lists. His search is interrupted by a man posing as an exterminator, who shoots Rigby in the arm and frisks the lists from the seemingly dead investigator.