This extraordinary episode opens with the dawn arrest of a man on suspicion of conspiracy to murder. The film documents the work of the lead detectives as they investigate and interview the suspect about his involvement in a plot to shoot a man. While driving to work, the victim was hit from behind by another vehicle. When he stepped out to inspect the damage he was shot in his leg by a close range sawn-off shotgun, sustaining life-threatening injuries. The police believe the case arises from a potential love triangle that has spiralled out of control. Detectives have 24 hours to gather enough evidence to charge or release him.

Police Constable Cheryldeen Liversidge and Police Constable Kat Alison investigate two strongly contrasting stories about harassment and domestic abuse. Domestic abuse takes up to 40% of police time nationally and is now a priority for Bedfordshire Police, having had a poor record in the past. A scorned wife has dumped an ex-partner's clothes in a charity shop, while another woman complains of a series of highly threatening messages from a man with a violent past. On the surface, two very different cases, but both officers turn the cases they are investigating into something of a crusade and are determined to get to the bottom of what really went on in the private relations between their suspects and the victims.

News spreads across the county about a suspected paedophile trying to abduct young children on their way home from school. Local press coverage has led to hundreds of calls from panicked parents to the police. With the culprit at large, cameras follow the Major Crime Unit as they lead the operation to arrest a third suspect following a nine-year-old girl's statement and an e-fit description. After two previous suspects have been released without charge, have they now got the right man? In the public protection unit, DC Annie Fowler and DC Selena Humphreys believe they have finally gathered enough evidence, including thousands of images and hundreds of videos of extreme child abuse, to ensure the suspect is remanded in prison pending a trial. Following his second arrest, he makes a frank and shocking confession. The detectives take this new information to the Crown Prosecution Service in the hope of preventing him from committing any more offences.

This episode opens with a young man accidentally dropping a large quantity of cocaine from his jacket pocket outside a petrol station - all caught on CCTV. On the case are hard-bitten Detective Constable Colin Knight and fresh-faced Police Constable Oly Tomlinson, who joined the team three months earlier. They get off to a promising start, tracking down the owner of the vehicle the passenger was travelling in. DC Knight brings in his chief suspect for questioning and discovers that, just like the man in the CCTV footage, he has a striking tattoo on the right side of his neck, but could it be a case of mistaken identity? Also brought in to the custody suite is Darren, a man arrested on suspicion of theft of meat from Marks & Spencer. As he is booked into custody it soon becomes apparent he is a heroin addict. Sympathetic Custody Sergeant Pete Fitz-Gibbon tries his best to persuade him to stay strong and get clean. Both cases provide a stark picture about the dark world of young people caught up in a cycle of drug addiction and crime in Luton and the challenges facing the police as they tackle it.

It's Saturday night in Luton, and Bedfordshire Police are dealing with drunken domestic disputes and a booze-fuelled fight. Police Constables Leanne Turner and Andy Parsons are sent out to investigate an alleged assault against a vulnerable and fragile 75-year-old man in a domestic dispute. The suspect is the man's private carer and has been living with him for the past seven years. When he made the 999 call, the elderly man alleged that he had been slapped in the head with an open palm. But when they arrive, PCs Leanne and Andy are confronted with a distressed victim who insists he does not want them to pursue the matter and who begs them to leave. At the police station, a Polish man arrested for a drunken row with his partner is admitted into custody. He's initially brought in for a 'breach of the peace' - to remove him from the situation and allow him to sober up and cool off - but things take an unexpectedly sinister turn when he whispers to the custody sergeant that he will kill his wife the following day.

A devout Muslim has been arrested on suspicion of assaulting his daughter with an iron, after she married a man he does not approve of. Bedfordshire Police have set up a dedicated `honour-based violence' unit at Luton, but the investigation falls to DC Rachel Chandler in CID. Will she succeed in finding the evidence before time runs out?

Drunken abuse, the theft of 98p's worth of fizzy drinks and the joyriding of a 45-seater bus are all in a day's work for acting sergeant Wil Taylor. Some can seem like a waste of police time, while others quickly become serious - such as the case of three sex workers who have been arrested during a raid on a local brothel. Are the women victims, possibly trafficked to the UK from Eastern Europe, or are they running the business and exploiting others? Last in the series