Sherlock Holmes in the 22nd Century S01 E08 The Scales of Justice

Dr. Grimsby Roylott uses a snake, not to kill his daughter, but to become a snake-man to steal nanobot technology to save his failed New London Zoo. The clues are a snake scale with hair, a sabotaged hovercraft, the Zoo financial records and the history of the animal rights activists, the Earth Sentinels.