Located in Democratic Republic of Congo, at the border of Rwanda, the volcano Nyiragongo is considered to be the most active in Africa. Its permanent lake of lava is the biggest of the planet. This volcanic phenomenon, rare and unknown, has been revealed to the public by Haroun Tazieff in 1958 in its movie “Devils’ Rendez-Vous”.

Its devastating eruptions threaten the 1 million inhabitants of the city of Goma, which is located at its bottom. The most important was in 1977. The most recent, in 2002, bothered the scientist community because of its violence.

For the Volcanologist Observatory of Goma, it’s a big challenge: increase the knowledge to anticipate the future eruptions and avoid catastrophes. It’s a very complex objective in a very instable region, geologically but also politically. Moreover, to go down inside the crater is very difficult and needs very special competences and experiments.

A team of French and Swiss volunteers, specialists of volcanologic expeditions has taken up the challenge: they go the closest to the boiling lake of lava, in the very heart of the volcano, in order to make samples and analyzes, and to install measuring tools.

This documentary tells the adventure of this exceptional collaboration between passionate volunteers and scientists in a place as dangerous as mythical.