The explosion is gigantic. A huge mushroom rises in the sky. A monstrous blast ravages the city. 90% of homes are damaged or destroyed; in a few seconds, 90,000 people are wiped out. Hiroshima marks the end of WW2 and the beginning of an era dominated by nuclear anxiety. To better understand the stakes and consequences linked to this turning point, one needs to go back 20 years, to the USA.Through worldwide and partly unreleased archives, talented director David Korn-Brzoza will bring a clear picture of this major event.