There was a time when the entire Po Valley, from the Alps to the Appennines, was covered by the sea. The sedimentation in the sea depths was responsible for the oldest rocks in Valstagna, at the foot of the Asiago Plateau. After emerging from the sea, the mountains were shaped and honed by atmospheric agents. The phenomenon of karstification has mainly shaped this landscape. By seeping through into the very depths of the earth, meteoric water has created galleries, underground channels and caves.. Among these is the important Oliero cave system, formed by the springs of Siori Covolo (Den of the Gentlemen) and Veci Covolo (Den of the Old Men), a unique complex which develops in a natural park that was founded in 1990. It is within this landscape that our documentary takes place; a speleological expedition to find the new underground frontiers that are helping geologists to extend their knowledge of the Karstic system, and develop new ways of protecting the environment. The main characters in this mission are Luigi Casati, the most successful Italian speleologo, and his teacher, Jean Jacques Bolanz,.