The Adventure of the Blue Carbuncle

On Christmas Eve, the invaluable Blue Carbuncle has been stolen from the Countess of Morcar’s hotel room. A plumber is arrested on the spot but the expensive missing gem is still nowhere to be found. Sherlock Holmes is called on to try to solve this puzzle.
"The Adventure of the Blue Carbuncle" is part of "The Adventure of Sherlock Holmes."
Sir Arthur Conan Doyle (1859-1930) was born in Scotland and studied medicine at the University of Edinburgh. After his studies, he worked as a ship’s surgeon on various boats. During the Second Boer War, he was an army doctor in South Africa. When he came back to the United Kingdom, he opened his own practice and started writing crime books. He is best known for his thrilling stories about the adventures of Sherlock Holmes. He published four novels and more than 50 short-stories starring the detective and Dr Watson, and they play an important role in the history of crime fiction. Other than the Sherlock Holmes series, Doyle wrote around thirty more books, in genres such as science-fiction, fantasy, historical novels, but also poetry, plays, and non-fiction.