Silent Witness

Fresh from her trip to the States, Nikki and the Lyell unit are called in to investigate an attack against a trans man. When two further attacks are reported, one leaving a potential witness, it becomes clear that the team is facing an outbreak of violence against the trans community. With the Lyell under increasing financial scrutiny and frustration growing between the team and the acting DCI, can they pull it together to find the killer before they strike again?

A slip-up from DCI Cramer results in the premature release of a suspect - and when his mistake becomes evident in the light of incriminating evidence, he tries to blame the Lyell for the oversight. With the team under increasing scrutiny, Thomas offers to bear the brunt of the pressure while the team focus on the search for the perpetrator. When his career in the field is threatened, will Thomas leave the Lyell to save his team?

After a teenage boy dies in a meth lab explosion, his inspirational head-teacher Noah Taylor resolves to confront the drug dealers praying on his community. Dangerous batches of new drugs are hitting the streets and it's down to Nikki, Jack, Clarissa and Thomas to deal with the consequent rise in overdoses.

When tragedy strikes at the heart of the Taylor family, it puts Noah on a collision course with the criminals behind the drugs. Meanwhile, one of the team's life is endangered when they become the victim of a knife attack.

A collection of dismembered body parts, covered in intricate Japanese tattoos, has been found in a Brighton waste dump. The team is called in to piece them together, painstakingly searching for clues that could lead them to the killer. Outside of the lab, Nikki has some news that she desperately wants to share with Matt.

The team struggle to find the final piece of the puzzle left behind by the murders in Brighton. At home, Nikki and Matt discuss their future together.

A shocking incident on a suburban street brings back painful memories for Jack, forcing him to revisit his past. As a member of the victim's family seeks justice of their own, forensic evidence discovered by the Lyell team suggests the involvement of a Northern Irish terror group, long thought inactive.

During the team's search for the killer, Jack works alongside an old friend from Northern Ireland, a fearless journalist who has dedicated her life to exposing the suspected organisation. As the team investigate further, they realise they have uncovered a complex conflict sustained by ties of loyalty, family and retribution.

Nikki is humiliated in court when a barrister accuses her of making a serious error in the case of a policeman who may or may not have been murdered. Meanwhile the team investigates the death of a medical researcher found in a canal with mysterious puncture marks on his body.

When Thomas sides against her findings on a controversial case, Nikki suspects foul play and takes steps to prove her theory. Jack and Clarissa follow a forensic trail connecting a dead researcher with a billionaire scientist and a secret testing programme.