Silent Witness

When Jack and Nikki enter a high-security prison to investigate the suspicious death of an inmate, the case and the victim's cellmate bring up disturbing memories for Nikki.

After a surprising breakthrough in Jay's case, Nikki struggles to accept that Scott may not be responsible; Meanwhile, DI Mason asks Jack and Nikki to investigate the death of someone close to the case.

When a swimming instructor is found murdered in her flat, trace evidence from the scene identifies two suspects, including the victim's ex-boyfriend, a former police officer; It's the first case for new recruit Adam.

Having traced Laura's last movements to a suburban house, the team struggle to identify the bodies buried in the garden; with a prowler seemingly on the loose, DI Meredith continues to suspect her former colleague.

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 anaesthetic at the time of the killing.

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.

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.

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 a 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.

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.