Boulton investigates when a young girl is approached and attacked on the way home from school. Her father, a property developer, has been having trouble with a gang involved in a pub protection racket. Unable to locate the prime suspect, Michael Hyde, Boulton poses as a competition representative to get the location from his wife. He and Carver travel up to Manchester on Hyde's trail. When they run into trouble at a local pub, they find themselves being rescued by none other than Frank Burnside, who left Sun Hill in mysterious circumstances five years ago. Burnside, who is actually undercover, tries to inadvertently help his former colleagues to find and capture Hyde, but the plan goes awry.
