Detectives Ash and Scribs investigate the murder of Helen McKee, who was the victim of a hit and run. Helen was secretary at a popular - and oversubscribed - local comprehensive school. With parents desperate to get their children into the school, she was the object of a good deal of attention. One man purposely started having an affair with her, just to improve his son's chance of acceptance. Equally, there are parents who blame her for their children's non-acceptance and may have wished her harm. They get a break in the case however when they learn that Helen was run over by her own car.