Aboard one of the most-advanced research ships in the world, on a seemingly unremarkable day, David Valentine decoded unusual signals underwater that gave him chills. As he scanned the seafloor with a deep-sea robot, he came across a trail of eerie-looking barrels that no one had seen before. He spent years sounding the alarm, but calls to the government went nowhere. He finally messaged Rosanna Xia, a reporter at the L.A. Times, who unearthed a startling truth: as many as half a million barrels of DDT waste had been quietly dumped into the ocean. The full environmental horror sharpens into even greater clarity once Xia starts to connect more dots: Sea lions have washed ashore with cancer in staggering numbers, and significant amounts of DDT can still be traced across the entire marine ecosystem. A new generation is now grasping the words of Rachel Carson, who first shook the world awake in 1962 with Silent Spring: “The obligation to endure … gives us the right to know.”