Hans Klug has a past he doesn't want revealed. A former East German border guard and American expert with the Ministry for State Security, Hans now ekes out a meager living as an interpreter. He is accosted on the street by a woman who demands 100,000 euros, or she will expose his role in the death years ago of an escapee at the frontier. Hans seeks assistance from his former colleagues, who in return for the money ask him to help locate the Black Vault, a chamber built by the Nazis beneath the streets of Berlin, filled with gold and diamonds looted from death camp victims. The key to the vault is held by an SS-man who escaped to America after the war. Only Hans, with his fluent English, is the right man for the job of traveling to America to track him down.
Many obstacles stand in Hans' way, including a former Communist party official, a neo-fascist history professor at a Bible college in Virginia, and the daughter of the SS-man. Hans must deal not only with these present perils but the shame of the past-his grandfather, a highly decorated SS-officer, helped destroy the Warsaw Ghetto.