When a successful British ghostwriter, The Ghost (Ewan McGregor), agrees to complete the memoirs of former British Prime Minister Adam Lang (Brosnan), his agent assures him it's the opportunity of a lifetime. But the project seems doomed from the start—not least because his predecessor on the project, Lang's long-term aide, died in a suspicious accident.
The Ghost flies out to work on the project, in the middle of winter, to an oceanfront house on an island off the U.S. Eastern seaboard. But the day after he arrives, a former British cabinet minister accuses Lang of authorizing the illegal seizure of suspected terrorists and handing them over for torture by the CIAa war crime.
The controversy brings reporters and protesters swarming to the island mansion where Lang is staying with his wife, Ruth (Olivia Williams), and his personal assistant (and mistress), Ameila (Kim Cattrall). As The Ghost works, he begins to uncover clues suggesting his predecessor may have stumbled on a dark secret linking Lang to the CIAand that somehow this information is hidden in the manuscript he left behind. Was Lang in the service of the American intelligence agency while he was Prime Minister? Was The Ghost's predecessor murdered because of the appalling truth he uncovered?