Silent Witness

While investigating a suspicious death in a prison, Nikki focuses her attention on the victim's cellmate, a dangerous criminal from her past.

As the team investigate a second death, Nikki's theory starts to fall apart. Can she put her fixation with Scott aside and find the killer?

In the first case for new recruit Adam, the murder of a swimming instructor leads the team to suspect her ex-boyfriend, a former cop. Meanwhile, Jack has an unexpected visitor.

Having traced Laura's last movements to a suburban house, the team work to identify the bodies buried in the garden. Meanwhile, Jack must choose between his brother and the truth.

Nikki, Jack and Adam are brought in to investigate the murder of a surgeon in a hospital. DNA evidence suggests the impossible when it implicates a patient who was under the anaesthetic at the time of the killing. Meanwhile Adam's friendship with the hospital director brings his impartiality into question.

With their suspect in a coma, and an attacker seemingly at large in the hospital, Nikki calls on Adam's expertise to help solve the case. Together the team make a breakthrough that hints at a medical conspiracy and exposes the lengths some are willing to go to protect their personal and professional reputations.

The murder of a promising boxer draws Nikki and Jack into the world of underground boxing. Meanwhile, Jack's brother Ryan is released from prison and comes to live with Jack and Conor, leaving Jack struggling to maintain peace with his brother and keeping the secret that he might be Cara's father. When Jack and Nikki's investigation hits something of a brick wall, they are introduced to forensic ecologist Simone. Her unique skills and lively personality prove to be exactly what the Lyell team need.

Jack, Nikki and Simone investigate another death connected to the underground boxing ring. Jack's loyalty is tested when he fears Ryan has put Cara in danger.

Nikki's students make an alarming discovery while dissecting a body donated for their training. The case that follows brings Nikki close to student Ollie, stirring dangerous feelings. Meanwhile, Jack and Simone investigate the care home where the victim died, but find themselves fighting to keep the residents alive when a diverted river floods the area.

Stranded in the flooded care home, Jack and Simone fight to keep the residents alive. Meanwhile, Nikki and Detective Galloway join the emergency relief effort and discover that Jack may be trapped with the killer. Shaken by events, and by Nikki's relationship with her student, Jack takes matters into his own hands.