Colonel March of Scotland Yard 1955-1956

Source: Web-Rip 480p. Episode The Sorcerer. Click on https://ok.ru/video/c5526477 to watch the rest of the episodes in full. Uploaded 26 of 26 episodes. A psychologist is found dead in a seemingly sealed room. Inspector March needs to decide who had the most reason to kill him, and how did they accomplish the task.