The Sentinel

Pete Garrison is a Secret Service agent and one of the personal bodyguards for First Lady of the United States Sarah Ballentine, with whom he is having an affair. He is one of the oldest and most experienced agents, having been involved in saving Ronald Reagan's life. His close friend and fellow agent, Charlie Merriweather is murdered. Garrison is told by a reliable informant that the killing of Merriweather is linked to an assassination plot against the President. The intelligence given by the informant reveals the existence of a mole with access to the President's security detail.