The Medway custody suite in Gillingham, Kent is one of the busiest in the country. The first programme in the series joins its staff, who process 40 suspected criminals every day.

From burglary to shop-lifting and assault to drugs possession, Custody Officer Sergeant Sean O'Conner and his team have seen generations progress through their criminal careers and witness a never-ending cycle of deprivation, drugs, crime, violence, and - for some of the women they meet - prostitution.

With frustration, resignation and sometimes anger - as well as flashes of frequently dark humour - ordinary police officers offer a raw insight into the harsh realities of policing modern Britain.