This novel's plot follows the professional career of a Prime Minister of Canada, James McCallum Howden, who faces various challenges of governance relating to foreign policy during the Cold War and domestic issues, such as immigration reform.

He and his wife Margaret are depicted as having a pleasant, passionless relationship, with the politician troubled by guilt over the memories of a past extramarital affair with his assistant, Milly Freedeman.

Three main storylines are intermingled in the novel, with the characters involved crossing paths at one point or another and influencing each other's lives indirectly through third parties or by feeling the consequences of each other's action.

The first storyline follows James Howden and the people from his immediate surroundings' interactions at work or personal affairs, such as the development of a romance between Howden's right-hand man Brian Richardson and Milly Freedeman, the second one describes a seemingly completely unrelated event on the other side of the country in Vancouver, BC, involving an illegal immigrant and his lawyer's attempts to gain him admission in the country, and the third deals with the imminent threat from a nuclear war and the diplomatic events set into motion between Canada and the United States as a result of their efforts to coordinate their defense against the Soviet Union and its satellite states.

The novel ends on a cliffhanger, with Howden preparing to give a speech in the House of Parliament about the future treaty with the U.S. that could change North America's political map forever.