2016, Russia, Cosmonaut Training Center. Another international crew (three Russian and two American cosmonauts), led by Commander Gennady Yashin, is preparing for launch to the ISS. During the preparation for the flight, it suddenly turns out that there is a psychological "time bomb" inside the crew, associated with serious difficulties in the family relations of the expedition participants and endangering not only the fulfillment of a mission of national importance, but also their lives.