This episode goes into Dr. Marcel Petiot, A.K.A. Dr. Satan, who earned this name for various reasons.
https://cvltnation.com/dr-satan-the-unbelievable-story-of-serial-killer-dr-marcel-petiot/
https://www.britannica.com/biography/Marcel-Petiot
https://historydaily.org/marcel-petiot-facts-stories-trivia/3
