The voices of the eyewitnesses reconstruct the massacre at the National Bank of Agriculture in Milan on 12 December 1969. The documentary aims to shed new light on the massacre carried out in Piazza Fontana, the failed explosion in Milan at the Banca Commerciale Italiana in Piazza della Scala, and the simultaneous explosion of three bombs that took place on the same day in Rome. These five attacks, that in 60 minutes hit the two major cities of Italy, inaugurated the long season of "strategy of tension" in Italy, forever marking the history of our country.