Special Branch officer Chief Insp. Rennie sends McNair undercover to Glasgow. He has learned that gangs have called a truce and become political. Rennie suspects explosive expert James Brodie is working behind the scenes to cause anarchy.
The Scottish Liberation Party is raising the level of violence in to England. Brodie murders the Scottish Secretary for State. John Mackie hands over a secret document of the Liberation Party planned actions to Patrick Harvey.
The Secretary of State for Scotland's dead body is dragged from the sea at Blackpool, wrapped in a Scottish flag. His replacement Lord Thorganby knows his goddaughter Sukey Dunmayne is raising cash and weapons for Scottish Liberation Party
MacNair discovers Colonel Cameron is the leader the SLP but is badly injured. The SLP move on Glasgow it's Brodie who hands over plans about French Communists bringing guns and Col. Cameron wanting Scotland to be a Communist dictatorship.