Spinster Nettie Soards goes missing. Ten days later her body is found in Dead Man's Canyon, and the next day an unidentified man is found dead not far away. The coroner rules the spinster died accidentally from falling off a cliff and the dead man was shot through the heart. Reports in the newspapers disagree with the coroner's verdict about the cause of death for Miss Soards and his dismissal of further investigation into the death of the unidentified man. Outraged by the coroner's decision, Maisy Malone and her best friend Mabel Normand decide to look into the spinster's death. They enlist new film star Roscoe Arbuckle to join them in their pursuit for justice for the two murder victims. Joining forces with Maisy are Detective Vince DeDonatis of the Venice Police, LA County Deputy Sheriff Jim Fox, Detective Sergeant Ed Browning of the LAPD, Ed's wife Nealy, and their favorite taxi driver Johnny Fowler. Together they search for clues and evidence of murder. They begin by looking at reels of stock footage cameraman Walter Wright had shot in Venice on the same day Nettie Soards disappeared. Maisy and Mabel find their first clue proving Murder on the Cutting Room Floor.