The first trailer for the upcoming documentary Emanuel, about the 2015 shooting at Charleston’s Emanuel AME Church, has been released. It’s a difficult—but essential—watch.

The film not only tells the true story of the shooting, but it examines the racial tensions in the Charleston area that might have contributed to the violence and its aftermath, as well as how many of the families affected by the violence in their community are embracing forgiveness. 

Steph Curry and Viola Davis are both executive producers for the film.