Summer, 1942 - Berkeley, California. While World War II is raging outside, a team of prominent physicists is talking bombs. Behind closed doors, American Robert Oppenheimer (1904-1967), Italian Enrico Fermi (1901-1954) and Hungarian Edward Teller (1908-2003) are discussing the most powerful bombs ever made, capable of winning the war. Contrary to general opinion, the team is not actually focusing on the atom bomb but rather on the hydrogen bomb, whose power is - at least theoretically - virtually unlimited. Just like the Sun, the H bomb draws its enormous power from the nuclear fusion of light nuclei, capable of releasing an amount of energy far greater than the A bomb, based on the splitting of heavy nuclei. But research was still at a very early stage back then, and three years later it was again the A bomb to make the headlines: the two specimens dropped on Japan killed 200,000 people. However, research into the H bomb continued and was the subject of a hot secret debate which then became public and reached its climax when a well-known test was carried out at the Marshall islands in November 1952. A firm believer in the potential of videos as educational tools, famous science historian Peter Galison introduces one of the most controversial scientific topics of the 20th century. Far from providing a merely technical contribution to the history of the H bomb, this documentary is an extremely clever report which features intriguing archive footage and alternates between voice-over narration and interviews (some of them with the main characters of the time), to give the audience a clear idea of the close relationship existing between scientific research and the history of mankind, between science and politics, science and culture. Because if science can shape history, the opposite is also unquestionably true.