A Danish journalist and a Swedish private investigator team up to reopen one of the most mysterious deaths of the 20th century: the 1961 plane crash that killed UN Secretary-General Dag Hammarskjöld. Their investigation begins with questions of sabotage — and ends somewhere darker. What they uncover is not just a Cold War cover-up, but something far worse. After more than fifty years, their findings lead the UN to revisit the case.