1929. And an Introduction by Admiral Sir Lewis Bayly. Illustrations from photographs and sketches and diagrams by Lieutenant J. E. Broome. An interesting account by Campbell in his own words of his experiences on board the mystery ships in which he served. Mystery ships were camouflaged to appear like peaceful merchant ships, but with real guns that were hidden until a few seconds before opening fire, or more frequently opening fire the instant the guns were disclosed. They cruised on the trade routes hoping to encounter an enemy submarine so that they might attract her attention, and then when the submarine came to the surface to sink her because of heavier armament. He relates the encounters with the enemy, both successful and unsuccessful and how his crew were the only ones who, not only once, but twice, succeeded in sinking an enemy submarine after their own ship had been torpedoed.