When teacher Lucy Chatham is abducted Nikki and Jack help police officers Andy Steemson and Karen Wretzy investigate the circumstances of her disappearance whilst Thomas assists abrasive DS Maureen Steele when ex-addict Tina Lunt is murdered. Doctor's daughter Jessica Timpson saw a car outside her house near the spot where Lucy was taken and her parents Nick and Ellie fear it may belong to Ellie's brother Alec Porter. Tina's death points to criminal boyfriend Wesley Beale whilst Lucy's sister's boyfriend Jasper Lampton is the key suspect when Lucy, his secret lover, is found dead. Forensic evidence suggests that both women were killed by the same man. Then Beale is murdered.