Watch Critical Incident

In Staffordshire, PC Claire Bond is left with life-changing injuries after a high-speed car chase ends with a criminal driver mowing her down. With both legs crushed and broken, Claire is forced to give up frontline policing for over a year - but grit and determination get her back on her feet.

In Cumbria, a police officer is mowed down by joyriders traveling at over 50mph. But despite his serious injuries - including losing an arm - Inspector Jon Sherlock is determined to get back on the beat. PCs Laura Jew and Rich Chant are patrolling Birmingham city center when an unprovoked attack sees Laura strangled and Rich's nose broken.

In Great Yarmouth, an undercover cop chasing down county lines drugs dealers is dragged along the road by a car as he tries to apprehend the driver. In York, there's a shock discovery for PC Rich Farrar as CCTV reveals that the suspected bike thief he just arrested was carrying a large kitchen knife.

A paramedic couple faces their worst nightmare when the wife hears over the radio that her husband has been attacked and knocked unconscious by a patient. The Manchester Tactical Vehicles Unit puts their lives in danger daily as they target vehicle crime using high-performance undercover cars.

A paramedic whose ambulance already had patients on board stops to assist in a road traffic accident. But as he tries to treat one of the people involved, he's headbutted so hard he's knocked unconscious. A rookie police officer experiences the darker side of the job when he is attacked by a patient he's guarding in a hospital.

PC Hayley Robinson has her ankle crushed after being driven at by a criminal in a car. But after five months of treatment, she's ready to go back to work. Elsewhere, fire crews across the country prepare for Bonfire Night - the worst night of the year for violent attacks on firefighters. And Saturday night revelry ends with a police officer needing stitches after an unprovoked attack.

A detective has a chemical thrown in her face as she tries to apprehend a gang of burglars, a police officer is injured as he tries to arrest a man who is threatening to kill officers with a machete, and a paramedic is headbutted by a patient.

In Edinburgh, PC Fraser Bell severs his artery while trying to restrain a youth, but his quick-thinking colleague saves his life by stemming the blood flow. In Manchester, PC Ian Bruce is part of a specialist team tackling vehicle crime. It's a dangerous job, and Ian finds himself alone and vulnerable as a gang he's chasing goes on the attack, using their car as a weapon.

In Wiltshire, an officer fears for his life when a drunk man turns violent and threatens to kill him. The terrifying ordeal lasts for nearly 20 minutes as PC Mat Baker waits for backup to arrive. Elsewhere, a burglar deliberately drives straight at an officer who is trying to arrest him, breaking his leg, and a paramedic is attacked by a man after she refuses to give him a lift home.

A police officer is stabbed in the arm as he tries to help a shopkeeper trapped inside a convenience store with a knifeman.