In a staid English seaside town after the Second World War, young Lynda grows up with her widowed father and younger sister. Rebellious Lynda has been swearing constantly from an early age. At sixteen, she becomes more exhibitionist and seeks out sexual encounters challenging the prevailing lower-middle class attitudes to sex. She eventually becomes pregnant by an acquaintance of her father.
Mary Morstan has received a pearl in the post every year since her father's disappearance. This leads Holmes and Watson to the truth about a secret pact between four convicts during the Indian Rebellion of 1857.