Dr. Grimesby Roylott is a fictional character from Sir Arthur Conan Doyle's detective story, "The Adventure of the Speckled Band." He is portrayed as a violent and aggressive man, known for his temper and his background as a doctor. Roylott is the stepfather of the story's protagonist, Helen Stoner, and is depicted as having a sinister influence over her life. Roylott resides at the dilapidated estate of Stoke Moran in Surrey, England. He is characterized by his unusual behavior and his connection to exotic animals, particularly a snake, which plays a crucial role in the plot. His actions and motivations drive the narrative, making him a key antagonist in the story.