What Happened In Vienna, Jack? by Daniel Kemp

This novel is the first in a four-book series called Lies and Consequences. It introduces Patrick West, a young police detective in London, England, to Jack Price, a British secret intelligence service operative. West has shot dead a known terrorist engaged in an armed robbery not far from Jack’s Soho apartment. Jack Price offers Patrick West more adventure if he joins the small but dedicated group he is in charge of. Jack is keeping a secret that was first heard in Vienna, Austria, at the end of WWII. Patrick accepts the offer, but he has not been told that someone is after the secret and is willing to kill to get it.