Slime is an ambiguous thing. It exists somewhere between a solid and liquid. It inspires revulsion even while it compels our fascination. It is a both a vehicle for pathogens and the strongest weapon in our immune system. Most of us know little about it and yet it is the substance on which our world turns. Slime exists at the interfaces of all things: between the different organs and layers in our bodies, and between the earth, water, and air in the environment. It is often produced in the fatal encounter between predator and prey, and it is a vital presence in the reproductive embrace between female and male. In this ground-breaking and fascinating book, Susanne Wedlich leads us on a scientific journey through the 3 billion year history of slime, from the part it played in the evolution of life on this planet to the way it might feature in the post-human future. She also explores the cultural and emotional significance of slime, from its starring role in the horror genre to its subtle influence on Art Nouveau. Slime is what connects Patricia Highsmith's fondness for snails, John Steinbeck's aversion to hagfish, and Emperor Hirohito's passion for jellyfish, as well as the curious mating practices of underwater gastropods and the miraculous functioning of the human gut. Written with authority, wit and eloquence, Slime brings this most nebulous and neglected of substances to life.