From the Trinity test in the New Mexico desert to the massive above-ground detonations of the 1950s and 60s, this film assembles restored footage of nuclear weapons tests, much of it declassified and unseen by the public before its release. Director Peter Kuran, who specialized in recovering and repairing decaying military archive film, tracks the arms race chronologically, from the Manhattan Project through the hydrogen bomb tests at Bikini Atoll and the Nevada desert, narrated by William Shatner in a flat, procedural tone that lets the footage do the talking. Mushroom clouds, shockwaves flattening test structures, and slow-motion fireballs fill most of the runtime, shot from angles and distances rarely released to the public at the time. The film does not editorialize much on the morality of the arms race; it treats the tests as a technical record, cataloging yields, dates, and locations. The cumulative effect is less argument than spectacle, an inventory of how much explosive power a handful of nations built and detonated within a few decades.