The speckled band

Helen Stoner seeks Sherlock Holmes' help fearing for her life after her sister Julia's mysterious death, marked by a strange whistle and mention of a 'speckled band.

' Holmes investigates the abusive Dr. Grimesby Roylott at Stoke Moran, discovering clues like a dummy bell-rope, ventilator, and saucer of milk.

Roylott used a venomous Indian swamp adder, lured by a whistle, to kill for inheritance; the snake ultimately kills him instead.