I must confess that, compared to WWII, I know relatively little about WWI. But this book seemed to be an interesting story, so I picked it up. Fortunately, it was a very interesting story indeed. It is the tale of the Wolf, a German merchant ship modified to carry guns, torpedoes, and mines. It was thus a wolf in sheep's clothing, capable of prowling the world's oceans in plain view without attracting undue attention at a time when Germany's navy was dominated by those of its enemies.
The Wolf's captain Karl Nerger presided over an amazing feat of seamanship as he kept his boat active for 415 days, traveled a distance equal to three times around the globe, sunken over a dozen ships, captured over 700 prisoners, and avoided enemy contact all without ever radioing home or setting foot in a harbor. After the first few months, everything the ship needed and used (e.g., fuel and food) was taken from captured ships. Their voyage started with them sneaking past the British naval blockage in the North Atlantic before sailing down to the tip of Africa, crossing into the Indian Ocean and on to the Pacific.
It was a herculean endeavor, with very low odds of success. Throughout the voyage, Nerger had to manage the delicate balance of the welfare of his prisoners (who included women and a child) with the success of his mission. Clearly, it would have been best to drop them off at some neutral port, but that would have betrayed his presence. Which, thanks to the Royal Navy not wanting to look bad, was hidden from the general public, making him much more effective. The book has a good amount of action in it, both in capturing ships/laying mines and in the contests between crew and captives. But it also delves deeply into the human side of what it was like to live on an isolated ship, forever in danger, forever on the edge of running out of supplies. Death was not a rare companion on this ship, but there were also joyous moments too (ironically, perhaps the most joyous centered around the 6-year old girl who was captured and made a mascot of sorts).
I won't say too much more for fear of giving away important details. Suffice to say, this is a very good book. It's not too technical, it covers a wide range of subjects, yet it maintains a coherent focus and a strong atmosphere of suspense that keeps the reader turning the pages. My only suggestion is to avoid the temptation to refer to the map at the beginning of the book that depicts their voyage and notable events as it's a bit of a spoiler. While I would never want to minimize the terrible nature of war and the ultimately brutal/lethal actions of the Wolf against her enemies (prisoners were treated well), this is an excellent book as it gives a great glimpse into not only an amazing WWI story, but into the lives of the people who lived it.