1968 of the last century. The calm and measured life of a small town located in the state of Florida, USA, and located on the coast of the Atlantic Ocean is turned upside down by another hurricane that suddenly came out of nowhere and also suddenly disappeared, washing away with coastal waves an ancient granite slab lying on the beach and disturbing for many years vacationers. This incident will be the beginning of a whole story that will change the life of a little boy named Denny, will change the lives of many people, will bring to the “clean water” those who some time ago had trust and respect in society. It will show how insignificant the modern military power of an entire country is compared to two representatives of a vanished civilization. The book teaches kindness, patriotism, love of children for parents and parents for children, both relatives and adopted ones, immense dedication for the sake of a friend, real army revenue. The exciting plot of the book is interesting for both children and adults and, after reading, keeps the reader in a state of anticipation for the further continuation of the story. Readers will imagine in the future becoming the owners of all three books of the Marcus Fastmower trilogy, in which the main character, the biorobot Marcus, will play a decisive role in battles with far away unfriendly representatives of a civilization long erased from the face of the earth.