In Bones Season 4, Episode 23, "The Girl in the Mask," Special Agent Seeley Booth investigates the murder of Sachi Nakamura, the sister of a Japanese detective friend, who was found in a Washington canal. The team discovers Sachi was an elite escort, leading them to investigate a deadly conspiracy while dealing with a guest expert's gender-related subplot. For the full episode synopsis, visit Bones Wiki . The Girl in the Mask | Bones Wiki | Fandom