The Earth is a huge spaceship, and humanity is its Crew. However, most of the Crew realized this simple truth only when the Aliens began regularly bombarding our planet with asteroids. After the next bombing, humanity received a message demanding to immediately solve all its problems - from international terrorism to environmental degradation, otherwise the next asteroid will fall in a densely populated area... A former cadet at the Higher School of the Military Space Forces, and now an officer of the Expert Group, Frol Pyatkin is obsessed with the idea of stopping the Aliens. Using his considerable mathematical abilities and survival skills in any conditions, Pyatkin is gradually getting closer to his goal.