Sir David Attenborough has spent a lifetime showing us the beauty of our planet, but when he filmed his documentary Ocean with David Attenborough, he witnessed something darker—reefs trampled and flattened by trawlers, great fish runs thinned, and once-pristine waters clouded by pollution and noise. Those months at sea made it impossible for him to ignore how quickly we are unravelling marine food webs and damaging habitats. Yet, the 99-year-old Attenborough reminds us there is still time to act