A prisoner is found dead in his cell and his death is regarded as suspicious. A riot follows and virtually destroys the prison, after two 'lifers' were questioned about the death. Helen Hewitt, who is deputy Governor of a female prison, is requested to become part of an investigation team looking into the mysterious death. Helen is offered the job of the Governor of the prison when the current governor is sacked. She uncovers cover-ups and she strives harder to get the truth.

Barfield Prison is given 60 million pounds to rebuild it after the riot. The prison is currently vulnerable, due to the helicopter wires being taken down due to the damage caused by the riot. A prisoner, Maynard, begins to plan his escape from prison. Meanwhile, another prisoner escapes, but he is then seen by Helen running back to the prison and she learns that he was a long distance running champion and she arranges for him to have regular training. While the prison is sorting out the problems of some of the prisoners, they are unprepared for Maynard and another prisoner to attempt their escape.

The prisoners begin to prepare for their trial, each of them being charged with the murder of the inmate who was found hanging in his cell. Fisher, a prisoner, applies for 'home-leave', not mentioning to Helen that his wife has requested a divorce and wants him to sign the deeds on his property over to her. Meanwhile, the trial of the prisoners for murder begins.

Barfield Prison begins to take shape again. Helen introduces the new black officers and they are met with mixed feelings from the staff and inmates. Helen also introduces a psychologist, Maureen Collins, who enlists the help of a prisoner to sort out the library. Alan Fisher is granted his home-leave, but he has some problems when he gets out. Helen discovers that he lied about the reason for his home-leave, which jeopardised his chances to move to an open prison.

The new prison is virtually completed and Helen demands that the new security systems are sorted out soon. The prisoners get drunk and one prisoner is attacked in the showers and his throat cut. Two other prisoners take advantage of the situation and attempt an escape. Helen realises that she could be replaced as the governor of Barfield, and has to fight to get the prison back in order before the Prison Services visit.