If Andy didn’t kill Susan, who did?

When human remains are found buried in a park, Crime Scene Examiner searches the area and finds student ID for Susan Clark, who went missing in 1988. Forensic tests prove that Susan was brutally murdered, and DCs Jacob Banks and Kezia Walker break the news to Susan’s stepmother Heather and father, Brian, who reveals he never reported Susan missing as he always thought she would return home, after storming out following a row. At that moment, Susan’s step-brother, Andy Hodges, arrives home and is shocked to hear the news.

Susan’s old friend Liz Flint tells Banksy she accused Susan of sleeping with her boyfriend, Rob Summers, who she later saw threatening Susan. Rob denies being violent with Susan, and his pal, Phillip Dowson, gives him an alibi. At Sun Hill, Heather breaks down when she recalls catching Susan and Andy in bed together on the night she vanished. Now the main suspect, Andy, is found in the park where Susan’s remains were buried. But a drunk and emotional Andy swears he couldn’t have killed Susan – he was in love with her.

When evidence proves that Andy was not in the UK when Susan was killed, Supt Heaton recalls a similar case from 20 years ago, where he had Ian Ellis sent down for the murder of Rebecca Clayton. As Heaton prepares to visit Ian at Longmarsh Prison, officers consider others he may have killed.