Documentary series following the traffic police as they enforce the law on Britain's roads. After one of the most reckless pursuits ever seen on the streets of Luton, a car thief tries to escape by climbing through somebody's window in the middle of the night. Not far from Luton, Sam and Shona are called to a bad crash along a country lane. Once the teenaged driver is freed from the wreckage of his car, he soon realises his troubles are not over, as his injured friends have discovered some unpleasant secrets he has been hiding from them.