In a case of home invasion by three men wielding a baseball bat, a family is subjected to a violent ordeal, late at night, in their own home. Rushing to the scene, police officers discover they have no idea why they were attacked.

Detectives suspect that a series of burglaries targeting the elderly and vulnerable might be the work of one man. CID Inspector Tom Smith must see if he can take this dangerous man off the streets.

When a man is found badly beaten on the side of a road with little recollection of what happened, Detective Sergeant Lee Marriner and Detective Constable Craig Weir must check all the available images to see if they can find any leads.

During a lads' night out, an interaction with a stranger leads to a violent attack that leaves one of them fighting for his life in hospital. Police must work to track down the assailant.

Detectives are tasked with bringing down the Norfolk-based Lewis drugs gang, and in particular, the man at the top of it who oversees the selling and dealing of crack cocaine and heroin at street level.

In Norwich, a specialist team of detectives are battling to bring down 'county line' gangs, which are flooding the city with illegal drugs brought in from beyond the county borders.