It is one of the most ambitious climate projects in the world: An 8,000-kilometer-long belt of trees is being planted across the African continent to halt the spread of the desert and provide millions of people with food, jobs, and a future. Along this still-incomplete green wall, Malian singer Inna Modja travels to meet people in Senegal, Mali, Nigeria, and Ethiopia. She talks with them about their fears, dreams, and hopes in a language that has always defined African culture: music. In this way, the film weaves together the soundtrack of the "Great Green Wall" in a collective melodic collage.