There is a seven-year war, Russian soldiers are forced to fight for the interests of France and Austria against Prussia. The midshipmen continue to selflessly serve the Motherland. One is on an expedition, the other is at court, and the third is sent to Venice to hand over a jewelry box. In fact, there is a message in the box, on which the future fate of Europe and Russia depends!

A 4-partmade-for-television feature film. Two young physicists, engaged in the problems of atmospheric electricity and the study of thunderstorm phenomena, both disciples of Professor Dankevich, a talented, straightforward, incorruptible man, unwavering in his principles. Dankevich endeavored to instill this uncompromising fight for honesty in science to the young scientists. And one of them, Sergey Krylov, lives up to the professor's expectations by continuing his work...