Prison officer Leigh lives for her job at Long Marsh men's prison. But when mouthy young Rose arrives, fresh out of training, C Wing will never be the same again.
Will Leigh cross the line between officer and criminal? Rose carries out a dangerous mission, and finds herself trapped in a potentially deadly double bind.
Leigh becomes increasingly isolated from her sceptical colleagues. A guilt-ridden Rose takes a chance to make amends. Toby's suspicions lead him to his own investigations.
With C Wing on lockdown, the prisoners' mental health reaches crisis point in an under-resourced and chaotic system. Meanwhile, Rose sees an opportunity, and Toby threatens to escalate his suspicions.
The prison officers at Long Marsh are set on making a fresh start, but Leigh hears a dangerous rumour about an undercover police officer on C Wing, The new governor orders Leigh to shut the operation down or the future of C Wing will be in jeopardy.
Leigh begins to doubt her team's loyalties when she discovers the identity of the undercover police officer. Meanwhile, Rose worries about her safety when it turns out that new arrival and double murderer Tyler Reeks has links to fellow prisoner Louis.
An accident in the prison workshop leads the inmates to go on strike, and C Wing descends into chaos. Leigh confronts the corrupt officer on her team. Rose is faced with a terrifying decision. And Jackie makes a shocking confession to Gary.
The deadly threat posed to Rose by Reeks forces Morgan to take matters into his own hands, setting him on a collision course with Leigh. Meanwhile, Rose tries to get close to prisoner Louis Acosta.
