On the morning of August 6, 1945, an American B-29 called the Enola Gay drops the first atomic bomb used in war on the Japanese city of Hiroshima. This BBC docudrama reconstructs that day through dramatized scenes of civilians, doctors, and city officials caught in the blast, intercut with interviews of Japanese survivors and the American airmen who flew the mission. Special-effects sequences show the fireball, the shockwave leveling wooden buildings, and the firestorm that followed, while the reenactments follow individuals such as a surgeon trying to treat burn victims with no working hospital left standing. The film also tracks the American side of the story, from the Manhattan Project scientists to President Truman's decision to authorize the bombing, and the crew's own uncertainty about what they had just done. Radiation sickness appears in the aftermath scenes as survivors who walked away from the blast begin dying in the following days. The film pairs eyewitness testimony with dramatization to put a human scale on a single weapon's destruction of an entire city.