In her first adventure for British Intelligence, Modesty and Willie Garvin are asked to protect ten million pounds worth of diamonds as they journey from London to Cairo. The fiendishly evil Gabriel and the deadly Mrs. Fothergill are planning to steal the diamonds with the help of their mercenary army, and it''s up to Modesty and Willie to escape capture, alert the British authorities, and as a last resort, do battle with Gabriel''s gang of assassins. It''s a thrilling ride as the two battle against impossible odds and a private army, and criss-cross the European continent.