Is the person building the world's most powerful AI someone you've never even heard of? While the media focuses on flashy CEOs, Demis Hassabis is quietly perfecting the 'last invention' humans will ever need to make. From a childhood chess prodigy to the man who solved a 50-year-old biological mystery, his story reveals a startling truth: we might be closer to curing all diseases than we are to understanding the very intelligence we've created.