In the Badlands of North Dakota, a team of scientists think they might have found the fossilized remains of animals killed on the day an asteroid struck Earth 66 million years ago. The evidence points to a catastrophic event, with a jumble of rare fossils, including a pterosaur embryo still in its shell and a well-preserved patch of triceratops skin, mixed in with tiny spheres of clay and glass that could be the fallout from the massive asteroid impact. Sir David Attenborough guides us on a search for clues that could give an unprecedented snapshot of what happened in the dinosaurs’ final moments on Earth.