Das Staatsgeheimnis (2001)

Lars Schelling runs a sushi bar in Berlin that was financed by the mafia. They now want their money back. Then suddenly his mother dies, and the next day he almost falls into the hands of kidnappers. Why? There's a lot of money involved that the Stasi put aside after the fall of communism to bribe politicians. And Lars possesses - without suspecting it - the code word for the Swiss bank...