In 1944, a smoking, battle-scarred B-24 Liberator bomber known as the Tulsamerican crashed into the choppy seas off the coast of Croatia, entombing three of its occupants under 135 feet of water. For years they were lost to the world — and their families. But in 2010, nearly seventy years after the crash, divers located the plane. And in 2017, the Department of Defense, aided by the Croatian Navy and some of the world's leading underwater archaeologists, set to work investigating the wreckage. Were the B-24s truly as dangerous as the nickname "the Flying Coffin" suggested? And what does that mean for the recovery of the fallen airmen? Now, NOVA joins a team of archaeologists on a dangerous mission to recover and identify their remains. They will deploy advanced mapping and diving technologies and sift through tons of sediment-eventually to find artifacts and other tantalizing clues. From the recovery of the remains to the subsequent forensics and DNA analysis of the remains in the laboratory, the story of the Tulsamerican is riveting and emotional. NOVA documents it all, including the moment a family hears the words they never expected to hear: "On behalf of a grateful nation..."