Watch: Ian Book Shares His Phone Call From Saints - The Spun

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 gives 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.