It's September 1931, and Adolf Hitler's live-in niece, Geli Raubal, lies dead on the floor of his Munich apartment at No. 16 Prinzregentenplatz. With Hitler's pistol by her side, it suits the Nazis to cover it up as a suicide.

This historical event forms the centrepiece for John Murray's novel in which he introduces Geli's lover, Bernard Connolly, who was in the apartment the night before. Geli was alive when he left. Hitler is devastated by Geli's death and furious when he finds out that Connolly has broken into his safe. With the Nazis in pursuit Connolly manages to escape.

Nearly ninety years later, John Scobie in Australia has the seemingly impossible task to find out what was stolen from Hitler's safe. Retracing Connolly's steps through Austria, Scotland, and Germany, Scobie picks up a trail of clues which leads him to the priceless object. But it's what Scobie discovers about himself that is the real surprise.