Modern humans evolved in Africa, then spread across every other continent on Earth, and this series traces the evidence behind that migration. It follows the Out of Africa theory, the leading scientific explanation for how our species left the continent and populated the rest of the world, using genetic data, fossil evidence, and interviews with researchers in the field. The series moves through the major waypoints of that spread, from the first departures out of Africa to the eventual settlement of Europe, Asia, Australia, and the Americas, looking at how small groups of people adapted to deserts, ice ages, and unfamiliar coastlines along the way. Presenter-led segments connect the genetic and archaeological findings to the physical landscapes where the migrations happened. The presenter and episode count are not specified in the available sources, but the throughline is consistent: reconstructing, region by region, how one African population became the ancestors of everyone alive today.