Location: HMP Y Glannau, and prisoner, Barry Hardy, picks up a bag of drugs off the floor after someone dropped them. A decision that is going to change the course of his life forever. Although his cellmate, Peter, tries to persuade him to get rid of the drugs, Barry thinks he knows better. A bloody incident on the wing means that the officers, Elin and Ned, worry about their jobs. And a new prisoner arrives. Kit Brennan isn't a stranger to everyone, and his appearance disturbs the equilibrium.
As Barry comes under pressure for his ill-advised decision to sell the drugs he discovered, he tries to reason with the real owner of the bag. When it makes the situation worse, he has no choice but to enter into a partnership with Kit. Peter is looking forward to his mother's visit, but circumstances beyond his control push him over the edge. And Elin and George's relationship heats up, but Elin has her doubts.
Barry has to face the reality of working for Kit. To make matters worse, he receives a visit from his little brother, Dale, who reveals that he is in serious financial trouble. Although Barry tries to help him, the conversation turns into an argument and Dale leaves under a cloud. Elin realizes that George has deceived her after all, and he makes it clear to her that she has no choice but to go against her principles.
Regretting his argument with Dale and with Kit controlling him like a puppet, the pressure is too much for Barry and he turns to violent means to get rid of his frustration. Peter receives bad news that leads him to a very dark place and Linda the chaplain's response to his statement breaks his heart. Elin discovers that Kit is behind the attempt to blackmail her, and she decides that her only way out is to challenge him face to face.
Barry discovers that his life is in danger because of the work he does for Kit, and when Dale walks into the wing as a prisoner, his head is in shatters. As Elin and Ned are called to see the Warden, they discover that the wing is being put under special measures and their jobs are at stake. Elin agrees to smuggle drugs into the prison for Kit, but when she discovers that Barry is working for Kit, she has one more chance to end the nightmare.
As Elin arrives at the prison in the morning, carrying drugs for Kit, she is shocked to hear that the prison is undergoing an inspection that day. With the drugs having to stay outside, Barry gets cold feet and decides he can't help Elin anymore. Kit loses patience with everyone who works for him and threatens Elin, but she finally manages to find the strength to break free.
