Writing Harry Blyth Other Credits Doddington Diamonds Characters 1922 The Further Exploits of Sexton Blake: The Mystery of the S.S. Olympic Characters 1919 The Thornton Jewel Mystery Characters 1915 The Great Cheque Fraud Characters 1915 The Stolen Heirlooms Characters 1915 Britain's Secret Treaty Characters 1914 The Kaiser's Spies Characters 1914 The Mystery of the Diamond Belt Writer 1914 Agent-readable