Franz Stangl ran Treblinka and Sobibor between 1942 and 1943, overseeing the killing of as many as 12,000 people a day, then vanished into South America for nearly three decades. This film follows the man who refused to let him disappear: Simon Wiesenthal, the Holocaust survivor turned Nazi hunter whose global search for Stangl became one of his defining cases. Archival footage, historian interviews, and documents trace the bureaucratic machinery Stangl built at the camps alongside the patient detective work, tips, and dead ends that eventually placed Wiesenthal on his trail in Brazil. The film moves between Treblinka's operational history and the mechanics of postwar escape networks that let officers like Stangl start new lives under false names. It closes with Stangl's capture and extradition, and with what his eventual trial testimony revealed about how the camp actually functioned. The result is as much a portrait of Wiesenthal's methods as it is an account of Stangl's crimes.