Just transferring into a squad run by her ex-Lover, DI Judy Hill is assigned to the case of a strangled schoolgirl.

DCI Lloyd and newly arrived DI Hill (who were lovers years before) investigate the murder of a schoolgirl. The girl was possibly having a sexual relationship with one of her teachers, one of whom is receiving anonymous love letters which puts his marriage at risk. This adds the man's wife to the list of possible suspects.