The story of artist R. H. Quaytman's discovery of an engraving hidden behind a famous artwork by Paul Klee. This book begins with artist R. H. Quaytman uncovering something startling about a picture by Paul Klee. Pasted beneath Klee's 1920 Angelus Novus - famous for its role in the writings of its first owner, Walter Benjamin - Quaytman found that Klee had interleaved a nineteenth-century engraving of Martin Luther, leaving just enough visible to provoke questions. Behind the Angel of History reveals why this hidden face matters, delving into the intertwined artistic, political, and theological issues consuming Germany in the wake of the Great War. With the Angelus Novus, Klee responded to a growing call for a new religious art. For Benjamin, Klee's Angelus became bound up with the prospect of meaningful dialogue among religions in Germany. Reflecting on Klee's, Benjamin's, and Quaytman's strategies of superimposing conflicting images, Annie Bourneuf reveals new dimensions of complexity in this iconic work and the writing it inspired.