When Albert Einstein died in 1955, pathologist Thomas Harvey removed his brain without permission and kept it in pieces for decades, hoping someone would eventually explain his genius. Neurophysiologist Mark Lythgoe and physicist Jim Al-Khalili take up that search, traveling to museums and research centers to examine preserved slides of Einstein's brain tissue alongside current neuroscience on intelligence and creativity. They find a brain with unusual patterns of folding and connectivity, particularly around the regions linked to spatial reasoning and abstract thought, and weigh that physical evidence against interviews with people who knew Einstein and accounts of his working habits and quirks. The film moves between the biographical, tracing how his ideas reshaped physics and our picture of the universe, and the clinical, asking how much of a mind like his comes from anatomy versus environment and experience. It settles on no single answer, treating Einstein's brain as an unusual specimen that raises more questions about genius than it resolves.