In The Notes, Orson Welles sets the stage for a haunting narrative from the Black Museum, a repository of murder artifacts housed within Scotland Yard. The episode opens with the discovery of a murder at a private supper club, the Royal Roost, where the proprietor, Matt Bolton, is found shot dead. Inspector Liggett and Sergeant Porter arrive at the scene, greeted by a chaotic atmosphere where the show must go on despite the violence that has just occurred. Amidst the confusion, they find a note tucked in Bolton's pocket that reads 'Kilroy was here,' a phrase with historical significance that hints at the killer's identity.