Ernst Ludwig Kirchner (1880 1938) is perhaps the most well-known Expressionist painter. His work reveals a phenomenon, which, to this extent, is rare for the art of the Modern era pictures painted on the reverse side of the canvas as a category of its own and it is explored in this book. Kirchner removed a large number of paintings from their frames, turned them over and used the reverse sides for further compositions. The initial spark for this publication came from a rediscovery, which came to light during the restoration of the reverse side of Kirchner s painting "Yellow Engelufer" (1913)."