The Frankfurt theater photographer Abisag Tüllmann (1935-1996) left her photographic documentation of the Beuys action Titus Andronicus / Iphigenie, which the artist performed on May 25, 1969, during the experimenta at the Frankfurt Theater am Turm, as a cohesive work to the Frankfurt Museum of Modern Art. In collaboration with the curator Mario Kramer, we are publishing this photographic collective work for the first time in book form. The action Titus Andronicus / Iphigenie holds particular significance in the oeuvre of Joseph Beuys. It is the only action by the artist that was conceived for the experiential space of the theater and references plays—Titus Andronicus by William Shakespeare and Iphigenie auf Tauris by Goethe—and is one of two actions in which Beuys interacted with a living animal. The white horse that stands on stage with Beuys.