Silent Witness - Season 3

A student is murdered and the police suspect it is the same person who killed lecturer Annabelle Evans. Sam is too close to the case and her emotion is clouding her judgement. She seeks the advice of her former mentor, Professor Leon Forman. Ryan believes that the killer is waiter and sometime student Marco Rossi, and that Annabelle's husband Martin is innocent. DI Connor learns that his suspicions are wrong about Martin killing his wife because she discovered he was having an affair. It was Annabelle herself who was adulterous. Sam and her partner, Trevor Stewart, deduce that Annabelle's body was likely to have been frozen, dressed, moved and smeared with animal blood. But why? It is as if the killer is playing a game with Sam, testing her skills. A clever and extremely dangerous killer may well be setting his sights on Sam herself.

Hidden secrets in a suburban, middle-class family come to light when a 17-year-old girl is found murdered. Gemma Boyd, a trainee estate agent, is found dead at the bottom of a staircase in an empty house. Mysterious phone calls are logged to her office and home. Are the police looking for a stalker or a lover? As the police and Sam Ryan investigate, dark truths about the family are brought to light. Sam learns that Gemma's mother, Suzy, threw her daughter out for having an illegitimate child at the age of 13, and the police unearth the fact that Gemma had already had another child by a boyfriend. Suzy, now remarried to Paul Franklin, is understandably upset about the death. Did she know that Paul was having an affair with Gemma? And who is making phone calls asking for Gemma? Sam is delighted to hear that her sister, Wyn, is to be married. But her pathologist partner, Dr. Trevor Stewart, is more concerned about her close relationship with surgeon James Reynolds.

When Suzy Franklin's first husband turns up on her doorstep after being released from prison, she greets him with a knife. As the relationship between Suzy and Paul disintegrates into accusation and deceit, Gemma's 13-year-old stepsister, Kate, remains isolated and desperate for her father's love. The police are also convinced that Boyd killed his daughter, Gemma – until DS Bradley discovers that Boyd was with his probation officer when the murder was committed. Their attention swiftly turns to another lover of Gemma's: wild boy Lee Bennett, after Sam learns that he was the last person to have sex with her. Sam has her own theory about what really happened, but it seems that the police are no nearer finding Gemma's killer. Who killed Gemma? A man from her past, an unknown stalker or someone closer to home?

A drugs war leads Sam into the murky world of dealers, undercover detectives and police corruption. Sam is called to a squalid flat where Maggie Collins and her baby daughter are found dead, the mother from a drug overdose, the baby from dehydration. Two weeks later, an explosion kills a local drug dealer. Sam's post-mortem reveals that the dealer had ingested the same drug as the dead mother. Sam thinks the cases are linked, but her theories are dismissed by DCI Hoskins, Head of the Drug Squad. Undeterred and unable to forget Maggie Collins' dead child, Sam continues her investigation, which leads her to the enigmatic Andy Fox who, on the surface, is a small-time drug dealer. But Sam discovers Fox's secret and his suspicions about Maggie's death.

After Fox is beaten up, he believes his attackers were officers. Does Sam realize her investigation could point to police corruption? When a second drug dealer is murdered, the police consider it the work of vigilantes. But Sam proves a link back to Maggie Collins. It's a link which leads her to a doctor with a secret past, a corrupt drugs rehabilitation worker and finally DCI Hoskins herself. As the death toll mounts, is the murderer someone who knew Maggie and seeks revenge for her death, or someone seeking to cover up their own involvement in her terrible demise?