Officers in North Yorkshire responding to a report of anti-social behaviour have to deal with a violent bystander as well, who breaks the leg of an officer while resisting arrest. In North Wales, a police van on its way to a domestic disturbance call-out is flagged down by a member of the public, who alerts the officers to a drunken confrontation between two groups of young people.

In Southampton, a Friday night in town descends into violence, and Sergeant Nicolas Tucker is left helpless on the floor after he is punched. Elsewhere in County Durham, PC Caryn Fairburn is on shift when she and her colleague are asked to respond to an argument.

A late-night patrol pulls over a man suspected of driving under the influence, but they soon find themselves dealing with much more. Meanwhile, officers responded to an emergency call by residents on an estate, but the atmosphere takes a worrying turn when the residents turn on the officers.

The return of the series exploring the rising number of assaults on police officers. PC Mike Davey and his police dog Bacca are faced with a man armed with knives. Meanwhile in London, a routine car stop late at night suddenly turns into a life-threatening incident when the driver jumps in his car and drives off and PC Nick Morley is left clinging to the car door.