Australian graduate students David Barison and Daniel Ross named this sweeping 2004 video essay after a Friedrich Hölderlin poem about the Danube that Martin Heidegger used as the basis for a 1942 lecture course, and while tracking the river from its Romanian mouth to its source in the Black Forest, they manage to consider some of the philosopher's main preoccupations (Greek mythology, Western civilization, technology) as well as his controversial interpretation of the Holocaust, recent ethnic conflicts in eastern Europe, and the difficulty of art representing history. Among their interview subjects are the charismatic Bernard Stiegler, Jacques Derrida associates Jean-Luc Nancy and Philippe Lacoue-Labarthe, and filmmaker Hans-Jürgen Syberberg. Unprecedented in its intellectual ambition, this is endlessly stimulating; it probably tries for too much, but it shames many other contemporary essays that try for too little. In English and subtitled French, German, and Croatian. Part one: 102 min.; part two: 87 min.