When an assassin claiming to have been in Dallas in '63 reaches out to Richard Whelan, a Secret Service agent guarding the most threatened President in History... No one believes the threat to the President is real, until a forgotten FBI file provides an unimpeachable link to a conspiracy stretching from JFK to Martin Luther King and into the present... And to an assassin's one and only opportunity, an impossible shot from an impossible distance - at the nation's first black president... As the assassin's finger tightens on the trigger, the one man who can stop him will have to choose between the ultimate personal sacrifice and a president who may already be doomed...