In his two previous novels, The Overseer (1998) and The Book of Q (2001), Jonathan Rabb showed a keen ability to look at a historical situation through both a wide angle and a close-up lens. In Rosa he manages to do the same for Berlin in 1919, just after World War I and before the rise of Nazism, showing how this moment in history affects both individuals in their private lives and groups of people in political movements.

For weeks, Detective Inspector Nikolai Hoffner and Hans Fichte, his young assistant, have been tracking a serial killer who has left four women dead with tell-tale mutilations carved on their backs. When a fifth victim is found, she turns out to be Rosa Luxemburg, a leader in the socialist movement that has brought about a revolution in Germany. Soon after Hoffner and Fichte determine that the markings on Luxemburg's back are fakes, her body is taken away and hidden by the Polpo, or political police. To resolve his case Hoffner must confront inter-departmental conflict, ethnic strife, a growing Nazi movement, and his own human failings. Rabb, who holds a master's degree in political theory, deftly explores the political philosophies behind socialism and Nazism, while giving an insightful reading of Hoffner's personal goals and demons.

The real Rosa Luxemburg was assassinated publicly in January, 1919, but her body was not found floating in the Landwehr Canal until May. Rosa is a thrilling account of what might have happened during those missing weeks.