September 1861: All is not as it seems. With these cryptic words, a shocking secret passed down from president to president comes to rest in the hands of Abraham Lincoln. And as the first bloody clashes of the Civil War unfold, Lincoln alone must decide how best to use this volatile knowledge: save thousands of American lives, or keep the young nation from being torn apart forever?

The present: In Utah, the fabled remains of Mormon pioneers whose nineteenth-century expedition across the desert met with a murderous end have been uncovered. In Washington, D.C., the official investigation of an international entrepreneur, an elder in the Mormon church, has sparked a political battle between the White House and a powerful United States senator. In Denmark, a Justice Department agent, missing in action, has fallen into the hands of a dangerous zealot - a man driven by divine visions to make a prophet's words reality. And in a matter of a few short hours, Cotton Malone has gone from quietly selling books at his shop in Denmark to dodging bullets in a high-speed boat chase.

All it takes is a phone call from his former boss in Washington, and suddenly the ex-agent is racing to rescue an informant carrying critical intelligence. It's just the kind of perilous business that Malone has been trying to leave behind, ever since he retired from the Justice Department. But once he draws enemy blood, Malone is plunged into a deadly conflict - a constitutional war secretly set in motion more than two hundred years ago by America's Founding Fathers.