A famous astrophysicist tragically dies on the lunar station during a scientific conference. Everyone believes that there was an accident. However, Richard Snow comes to the conclusion that the death of the extravagant professor is not a whim of fate, but a crime. Unexplained facts and incredible events quickly draw the special agent into an unprecedented scientific detective search fraught with mortal danger. A scrupulous comparison of facts, mysterious murders and disappearances, the pursuit of the elusive shadow of a criminal on the Moon, on Earth, in unimaginable cosmic distances, the professor’s fantastic invention - the toposcope - all this is woven into a tight knot. In the meantime, scientists are arguing about the existence of aliens, some of the earthlings have already made contact...