As any sailor knows, life at sea is hazardous under even normal circumstances. In times of war with an enemy intent on killing and sinking you it is infinitely more so. David Blackmore has researched 100 extreme cases over the span of history and written graphic descriptions covering the background, the events and the tragic consequences. Many were the result of enemy action, others (too many) straight human error and the remainder were caused by act of God, not least the weather.