We present to the attention of readers a book dedicated to the creation of the first generation of domestic manned underwater vehicles, designed to operate at depths of more than 1000 m. The history of the submarine fleet, despite the flurry of recent publications, remains little known not only to the general public, but also to people throughout their lives who have worked in the industry Meanwhile. the complexity of the tasks facing participants in work on “deep-sea topics” - as it was called in the Ministry of Shipbuilding Industry - can only be compared with those that the creators of spaceships had to solve. But if the names of Korolev and Gagarin are known to the whole world, then about the chief designer of deep-sea technology, Yuri The reader will learn for the first time about Konstantinovich Sapozhkov or the first deep-sea captain Mikhail Nikolaevich Diomidov from this book. The author tried to show the process of creating and testing an underwater vehicle as a complex technical system, which is, in turn, part of an even more complex complex of underwater technical work. Living and clear examples show how oblivion or underestimation of a systematic approach made it difficult to create and use deep-sea technology