The Adventure of the Beryl Coronet

A wealthy banker, Mr. Alexander Holder, asks Holmes for help. He had lent a client £50,000 using a priceless beryl coronet (a jeweled crown) as security. Holder foolishly kept the coronet at home. One night, he caught his son, Arthur, holding the coronet with several beryls missing. Arthur refused to explain, so Holder had him arrested for theft. Holmes investigates and discovers that the real culprit was Holder's niece, Mary, who secretly needed money for her lover, Sir George Burnwell. Arthur had tried to stop Mary from stealing the beryls and was repairing the coronet when his father saw him. Holmes recovers the missing beryls, clears Arthur's name, and the son is released.