The book by marine biologist Danna Stough is devoted to a topic that does not receive too much attention in popular science literature, namely the evolution and biology of unique marine invertebrates - cephalopods. These creatures, which appeared at the dawn of multicellular life, gave rise to many diverse forms, won a dominant position in the ancient seas, survived several mass extinctions, including the Great Permian extinction, which killed 96% of marine animal species, and have survived to the present day as such intelligent, complex animals like octopuses, squids and cuttlefish. The evolutionary history of cephalopods is seen in close connection with the development of many other creatures, including their eternal enemies - fish and, later, marine mammals. In his narration, the author cites a lot of paleontological data, talks about scientific mysteries and often contradictory hypotheses, discusses the reasons for the extinction of ammonoids and the successful evolution of coleoids and nautiloids. Readers will find many amazing stories about the intelligence and ingenuity of octopuses, the wonders of color camouflage of cuttlefish, myths, telling about giant sea monsters, about researchers who dedicated their lives to these amazing creatures.