Charismatic, erratic, egocentric, almost forgotten... Sergej Tschachotin was a scientist of international repute, friend to Pavlov and Einstein, revolutionary and pacifist. His private life was equally packed: five marriages, eight sons. SERGEJ IN THE URN tells the story of Tschachotin’s epic existence – from 1883 to 1973 – through the memories of four of those sons. They speak of Tschachotin’s role as a cancer researcher, his participation in anti-totalitarian propaganda movements, and his crusade against the arms race. Filmmaker Boris Hars-Tschachotin, Sergej’s great-grandson, weaves together an intimate, tortured family saga that mirrors the myriad contradictions and possibilities of the 20th century. Seeking resolution, he attempts to reunite his scattered family in a small Corsican village to bury the ashes contained in Sergej’s urn. This plan, however, like the painful period from Russian Revolution to the beginning of the 21st century it describes, is always on the verge of falling catastrophically apart.