V.V. Notebook with Drawings in the Margins

January - March 1902. United States of America - Russia. Young American engineer Andrew Timothy invents a super-speed electric motor for a submarine. The military commission rejects the invention because, in their opinion, it requires further development. However, an unknown... person learns about the unique engine and begins to blackmail Timothy. The persecution frightens the engineer. Moreover, he is in dire need of money. Fortunately, a Russian artist, Vasily Vereshchagin, arrives in San Francisco, where Timothy lives. Timothy finds out that Vereshchagin is a former naval officer, so he must understand something about ships and submarines. He meets with Vereshchagin and says he is ready to sell his invention to Russia. Vereshchagin suggests that he apply to the Russian consulate in Washington. Timothy agrees. But on the way to Washington, right in the train car, the unknown person kills the engineer and steals all his belongings. Also on this train is Zagorsky with his loyal companion Gantszalin, and apparently, they will have to get involved once again in a complicated investigation filled with dangerous adventures.