When an Englishwoman receives mysterious gifts of pearls and a letter promising to right wrongs done to her, she calls upon Sherlock Holmes and Dr. Watson to investigate. Who is sending the beautiful Miss Morstan a rare and priceless pearl each year? Holmes and Watson pursue Indian treasures, and murders whose ominous trademark is 'the sign of four'. It is in this, the second Holmes novel that the great detective fully comes to life ─as a melancholic and an inscrutable master of deduction.