Holmes' client is Helen Stoner, a 32-year-old spinster who lives with her stepfather: Dr. Grimesby Roylott of Stoke Moran. Dr Roylott is the last survivor of what was a wealthy but dissolute and violent tempered aristocratic Anglo-Saxon family of Surrey. After returning from India where he had a large medical practice and had served a jail sentence for killing his native Butler in a fit of rage, Roylott a widower settles with his two stepdaughters in the broken-down ancestral manor-all that is left of estates that had extended into Berkshire and Hampshire.
The doctor becomes notorious for terrorizing the local village because of his quarrelsome personality and violent temper. He allows gypsies to camp on his property, and a cheetah and a baboon also have the run of the property, for Dr. Roylott keeps exotic pets from India.
Dr. Roylott has required Miss Stoner, who is engaged to be married, to move into the bedroom next to his in his heavily mortgaged ancestral home in Stoke Moran. This room was the one in which two years before, Helen's twin sister Julia had died under mysterious and dramatic circumstances just prior to her wedding uttering the last words "The band! The speckled band!" before she died.