On August 29, 1949, the first Soviet test bomb, dubbed First Lightning, exploded in the deserts of Kazakhstan. The startling event was not simply a technical experiment that confirmed the ability of the Soviet Union to build nuclear bombs during a period when the United States held a steadfast monopoly; it was also an international event that marked the beginning of an arms race that would ultimately lead to nuclear proliferation beyond the two superpowers. Following a trail of espionage, secrecy, deception, political brinkmanship, and technical innovation, Michael D. Gordin challenges conventional technology-centered nuclear histories by looking at the prominent roles that atomic intelligence and other forms of information play in the uncertainties of nuclear arms development and political decision-making. With the use of newly opened archives, Red Cloud at Dawn focuses on the extraordinary story of First Lightning to provide a fresh understanding of the origins of the nuclear arms race, as well as the all-too-urgent problem of proliferation.