Claude Lanzmann spent twelve years creating Shoah (1985), a groundbreaking work that revolutionised the representation of the Holocaust in cinema. Four decades later, filmmaker Guillaume Ribot immerses himself in over 220 hours of unreleased footage from the original filming. Lanzmann’s quest to capture the reality of the Holocaust led him to interview victims, witnesses and perpetrators from all over the world. He embarked on an unparalleled journey which, overcoming doubts, setbacks and false leads, finally resulted in a landmark of film history. In 2023, the film was added to the UNESCO Memory of the World Register. Now, Ribot uses only Lanzmann’s own words drawn from his memoirs and previously unseen excerpts from his filming material to pay homage to one of cinema’s masterpieces and to the director’s relentless pursuit of telling the untold.