On a routine intelligence gathering mission in Tehran, Jack Ryan, Jr, has lunch with his oldest friend, Seth Gregory, an engineer overseeing a transcontinental railway project. As they part, Seth slips Jack a key, along with a perplexing message. The next day Jack is summoned to an apartment where two men claim Seth has disappeared - gone to ground with funds for a vital intelligence operation. Jack's oldest friend has turned, they insist. They leave Jack with a warning: If you hear from Seth Gregory, call us immediately. And do not get involved. But they don't know Jack. He won't abandon a friend in need. Racing against the clock, Jack must unravel the mystery: Who is friend and who is foe? Before it's over, Jack Ryan, Jr, may have to choose between his loyalty to Seth and his loyalty to America.
