At 10:39 PM of October 9, 1963, a landslide of 250 million cubic meters of land is detached from Mount Toc and falls into the artificial reservoir created by the Vajont dam, located in the northern mountains of the Veneto region (Italy). The landslide raises a hundred-meter-long wave that crosses the dam and within a few minutes falls on the Longarone village, at the foot of the dam. The country is completely destroyed. Nearly 2000 people in a few seconds pass from sleep to death. The film-documentary proposes, almost 50 years after the tragedy, one of the most serious European catastrophes since the post-war period to date. Within the documentary, different and significant are the testimonies of the protagonists of that dramatic event, which has destroyed entire countries and villages. The basis of the film is the extraordinary repertoire material, mostly unpublished. Also, inside the documentary, there is a touching testimony of Giampaolo Pansa, then sent to the Press.