The author talks about the famous pirate raids of German ships in the 20th century. These powerful floating arsenals, disguised as harmless neutral cargo ships, skillfully and systematically brought chaos into the enemy's merchant shipping system. In the first three most successful years for them, the raiders sank almost three times as many ships as the entire German surface fleet. The book is based on authentic materials; official reports, logbook entries, and eyewitness accounts are presented.