By pure chance scientists discover a signal from space that could be an statement from rational beings. How can we read this message knowing nothing about the senders? What if we are not even sure whether they exist? "His Master's Voice" is not a typical book. It lacks an adventure plot, yet struggle with the mystery rivets readers' attention more than in many adventure books, especially since the encounter with the unknown provokes elementary questions about the nature of the world, nature of man and reasons for defects of Being.