World War II's Manhattan Project required the refinement of massive amounts of uranium, and St. Louis-based Mallinckrodt Chemical Works took on the job. As a result, the chemical company's employees would become some of the most contaminated nuclear workers in history. This documentary explores the legacy that St. Louis is still coping with, from workers who became ill - to the challenges of dealing with the fallout of creating some of the world's first nuclear waste. The story is not unique to St. Louis, as more than 300 facilities across America would become part of the race to build the bomb, and be forced to deal with many of the same issues. A detailed look into what some of the men and women went through inside these plants, and how decisions made in the past, effect us all today.

Before the creation of the secret cities of Los Alamos, Oak Ridge and Hanford, the Manhattan Project hired the Mallinckrodt Chemical Works of St. Louis to refine the first uranium used in the atomic bomb dropped on Hiroshima. For the next two decades, Mallinckrodt continued its classified work for the Atomic Energy Commission during the Cold War. The resulting radioactive waste contaminated numerous locations in the St. Louis area some of which have not been cleaned up 70 years after the end of World War II. Told through the eyes of an overexposed worker, the story expands through a series of interviews that careen down a toxic pathway leading to a fiery terminus at a smoldering, radioactively-contaminated landfill. The First Secret City reveals a forgotten history and its continuing impact on the community in the 21st Century, uncovering past wrongdoing and documenting the renewed struggles to confront the issue.