In this electrifying #1 New York Times bestselling thriller from Tom Clancy, a silent war between the USA and Russia will decide the fate of the world-and Jack Ryan is behind enemy lines. Two men possess vital data on Russia's Star Wars missile defense system. One of them is CARDINAL-America's highest agent in the Kremlin-and he's about to be terminated by the KGB. The other is the one American who can save CARDINAL and lead the world to the brink of peace...or war.