The story's set in motion when the all-but-forgotten spymaster Stewart Banquo recruits Peter Johnson, a dissolute, slightly morally bankrupt journalist for a liberal news organization, to travel to Iran and assassinate an Iranian scientist whom the CIA suspects of developing  nuclear weapons.  Johnson's attempt fails, and he is rescued by the CIA agents who trained him. 

Back in the states, Johnson and his CIA cohorts lead a team of federal agents in tracking a group of suspected Iranian terrorists in New York who, as it turns out, are not only in possession of a suitcase nuke, but are also planning to commit biological terrorism by dispersing "The Grunge," a highly radioactive chemical, on the New York city subways, as well as along the city's sidewalks.  When the journalist's only daughter is kidnapped by the Iranians, Johnson and company race against time  to save her, as well as the city of New York.