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Firebrand Labour leader Michael Murray is swept into office on a tide of rhetoric. His first act is to "reform education", but it looks suspiciously like a personal vendetta against Mr. Weller, the headmaster who had once sent him, as a boy, to a special school for disturbed children. When Murray is summoned by the renowned political theorist, Mervyn Sloan, he is told that great things are expected of him. But Sloan also firmly insists that a general strike be called in Murray's city to challenge the Conservative Government. When one of Murray's council members, who has a weakness for the bottle, fails to ensure pickets are sent to one particular school, a disastrous conflict ensues between Murray and Jim Nelson, who is unfortunately headmaster of a school for special needs children.

Michael Murray is beginning to realise that his new-found political "friends" are not being entirely above-board with him. Jim Nelson, meanwhile, gains some respite from Murray's persecution when he becomes a local hero in a tragic accident. Though his attempt to save his pupil, Robbie Burns, is not successful, his efforts earn him the undying loyalty of Robbie's father, Norman, and his formidable brothers. After a time, however, Murray resumes the pressure and Jim begins to come unravelled, manifesting as a new phobia for bridges. His doctor refers him to a psychiatrist, Dr. Goldup. At the hotel where Murray is carrying out most of his plotting, his eye is caught by a new arrival, a beautiful and poised woman called Barbara Douglas.

Sloane and Barnes announce matter-of-factly that explosive racial violence shall be provoked in the city. When Murray denounces them and begins to storm out of the room, Barnes asks if the name Eileen Critchley means anything to him. Murray freezes on the spot and goes into spastic twitches. Jim Nelson decides he needs a holiday at term break, to get away from the pressure of Murray's pickets, and plans an itinerary that avoids crossing any bridges. Murray is falling under the spell of Barbara Douglas, who keeps him at arm's length. Meanwhile, she visits Michael's mother, pretending to be a social worker, and leaves a note for Michael--signed "Eileen Critchley". Franky has finally had enough. He abandons Michael and drives off with the council car, in order to take his wife and children, as well as his mother, on an impromptu holiday to the seaside.

Michael Murray has reached panic level, and sends the researcher, Philip, on a mission to find three people: his missing brother Franky (along with the council car), his mother, and Eileen Critchley. Frank Twist catches up with Jim Nelson to tell him that an important local party meeting has been called. The meeting is to be packed with "new members" consisting of the trouble-makers under Peter's direction. Barbara's attempt to obtain Mr. Weller's old school records for Michael Murray and Eileen Critchley fail, and Weller deposits the incriminating evidence with Jim Nelson, on the night before he leaves on holiday. Lou Barnes tells Barbara that they now have Murray at breaking point, but because they do not yet have Weller's documents, Murray must be "relaxed" a bit, and Barbara will have to do the job. It looks like it's Michael's lucky night.

The Nelsons finally arrive in North Wales, thinking they have escaped their tormentors. Trouble is pursuing them, however, and mein Host at the holiday camp isn't without his problematic side, either.

It starts to dawn on Michael and Jim that they are pawns in a much bigger game. Barbara questions who her real allies are.

Friday is the day designated for the showdown. Michael has had the local Labour Party meeting called to have Jim Nelson removed from membership; Lou Barnes has decreed this same day for Michael Murray's destruction.