Recent stunning advances in AI have given us a new wave of disarmingly human-like chatbots, such as ChatGPT, Claude and Gemini that appear to be able to talk and reason like us - and they are beginning to transform everything we do. It is vital we understand how they work. Can AI 'think', 'know' and 'understand'? Could it manipulate you, and if so, what might it make you do? Whose interests does it represent? And when will it be able to act in the real world for itself? To answer these questions, neuroscientist and AI researcher Christopher Summerfield takes us under the bonnet and charts the evolution of AI, from its earliest origins in the seventeenth century to today's Large Language Models, which not only put the knowledge of all the world's experts at your fingertips but already can write and execute code, and soon will be able to run our daily lives better than we can. The resulting book is the most accessible, up-to-date and authoritative exploration of this radical new technology. Ultimately, armed with an understanding of AI's mysterious inner workings, we can begin to grapple with the existential question of our age: have we written ourselves out of history or is a technological utopia ahead?.