Cameras follow the work of the detention officers and custody sergeants in their daily battle to keep the lock up on an even keel.
Two thirds of young offenders usually grow out of a life of crime, but in the first of this eight-part series, Sgt Jane Biglin has a guest list of regular clients - the dangerous ASBO breaker who gives an Oscar-winning performance to get out of jail; the prostitute who finds refuge in the cells; and the young thief, a heroin addict since he was 15, who goes cold turkey.
Sgt Rich West deals with a drunken teenage graffiti artist who has run riot through his mother's house, a man who has given himself a headache by hitting the cell door, and a regular visitor to the station whose breathalyser reading is five times over the limit.
Sgt Dave Beer comes across two regular offenders - an 11-year-old girl arrested for assault and a 12-year-old who threatened to set fire to her care worker. Officers deal with a newcomer to the custody suite who is too small to reach the desk to sign his name, and a teenager charged with burgling a pensioner, while a mother begs her son to give up alcohol for the sake of his family.
It's a round of medical emergencies and digestive dilemmas for Sgt Peter Swann, famed in Humberside Police for his everlasting appetite. The sergeant finds himself face to face with a cheese thief who steals to feed his drugs habit; a burglar who won't eat or drink because he has swallowed his loot and refuses to go through the evidential 'motions'; and the teenage boozer who wants to be a copper and is so drunk she can't keep anything down.
After running a red light with the cops in tow, a drunk and strangely-garbed student faces a career in tatters. It's a long expensive road back to Vietnam for the illegal cannabis grower who has paid a gang 6,000 euros to get him to the UK. And in a race against time, can the cops get the CCTV evidence on a shoplifter and save her box of legally-paid-for cornettos before meltdown?
A copper by name and a copper by nature, stand-in sergeant Stu Constable faces a prisoner's ultimate weapon, bodily fluids, in a dirty protest at the suite. When an old soldier collapses with a suspected stroke, the sergeant has to contend with the hospital medics who send the veteran back to the Lock Up. And will Sgt Constable solve the mystery of the 5ft-nothing drunk claiming to be a millionaire jockey who rode 700 winners?
Sgt Goode has to deal with a youngster who refuses to tell him his name. He also has to breathalyse a squaddie who is brought in. He also has to charge an addict who will return to prison for a fortieth time in his life.