There's an alert at HMP Downview women's prison when repeat offender Collette O'Flaherty, distraught at missing out on a place at the prisoners' family day, takes a fellow inmate hostage. A prisoner at HMP Portland hears false rumours that he is a sex offender - and suspects the culprit spreading the lies is a new officer. The inmates at HMP Bullingdon look forward to Friday, when they receive small treats like chocolate and shower gel - but dealing in these items quickly leads to violence.

We follow Jamie Smith and the dedicated search team of HMP Isle of Wight as they track down a USB rumoured to contain child pornography.

The reality of life inside one Britain's 30 Young Offenders Institutions - HMYOI Deerbolt in County Durham. Following weeks of violence and unrest, caused by the influx of drugs and mobile phone being smuggled in, a clampdown has been put in force. Acting on intelligence that inmates have been targeting the weekly Muslim prayer service to exchange illicit items, officers, along with the Imam Muhammad Meah, face a battle to regain control. Elsewhere at HMP Bullingdon, officers in the Segregation Unit are dealing with a prisoner on a Dirty Protest who refuses to leave the wing and attempt to appease the situation with newly recruited prison officer Beth Buchanan. Last in the series.