Charles Foster wanted to know what it was like to be a beast: a badger, an otter, a deer, a fox, a swift. What it was really like. And through knowing what it was like he wanted to get down and grapple with the beast in us all. So he tried it out; he lived life as a badger for six weeks, sleeping in a dirt hole and eating earthworms, he came face to face with shrimps as he lived like an otter and he spent hours curled up in a back garden in East London and rooting in bins like an urban fox. A passionate naturalist, Foster realises that every creature creates a different world in its brain and lives in that world. As humans, we share sensory outputs, lights, smells and sound, but trying to explore what it is actually like to live in another of these worlds, belonging to another species, is a fascinating and unique neuro-scientific challenge. For Foster it is also a literary challenge. Looking at what science can tell us about what happens in a fox's or badger's brain when it picks up a scent, he then uses this to imagine their world for us, to write it through their eyes or rather through the eyes of Charles the beast. An intimate look at the life of animals, neuroscience, psychology, nature writing, memoir and more, it is a journey of extraordinary thrills and surprises, containing wonderful moments of humour and joy, but also providing important lessons for all of us who share life on this precious planet.