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.
His pursuit of the truth will lead him across Iran, through the war-torn Caucasus, and finally deep into territory coveted by the increasingly aggressive Russian Federation. Along the way, Jack is joined by Seth's primary agent, Ysabel, a enigmatic Iranian woman who seems to be his only clue to Seth's whereabouts.
Jack soon finds himself…
