Today, like a ship entering the storm, the world faces climate change induced collapse. Once You Know, by director Emmanuel Cappellin, is a poetic and poignant exploration of how four of the world’s leading climate scientists and energy experts find truth, chaos, and hope in their work.

To stay below a 1.5 degree increase in global temperature, we must leave between 60 and 80% of fossil fuel reserves in the ground. Which energies should be preferred to replace oil, gas and coal? Renewable energies or nuclear energy?

In a few years, wind turbines have become the symbol of the energy transition. Is the dream in line with reality? Professionals, experts and local residents reveal the other side of the story.