The Galapagos Islands drew global attention after Charles Darwin's 1835 visit, but Darwin worked only from the surface and shoreline, without any way to see what lived in the deep water surrounding the islands. This program, narrated by Roscoe Lee Browne, sends modern submersibles down into those depths off the Ecuadorian coast, letting scientists spend extended stretches on the sea floor rather than a single dive's worth of minutes. The footage follows researchers as they encounter organisms new to science, some collected and brought back to the surface for classification, alongside the more familiar iguanas, tortoises, and finches that made the islands famous in the first place. The camera spends time on the underwater terrain itself, the volcanic rock formations and thermal vents that shape which species can survive there, treating the ocean floor as its own unexplored territory rather than backdrop. The contrast the program keeps returning to is simple: Darwin saw a fraction of this ecosystem, and a large part of what actually lives around the Galapagos was invisible to him entirely.