Darryl is out in Exeter looking for a motorist who's bashed up a lamppost and a parked car before driving off. Unsure as to whether he has abandoned his vehicle, Murphy is on hand, but turns out not to be needed after all as witnesses managed to grab the number, and now they have an owner's address to check out. Sure enough, a bashed up car is parked outside – and the challenge now is to find out who was driving, and whether they were bevvied up when they were doing it. A knock on the door reveals a young man who, confused at the arrivals, says at first that he has been out, and then claims that he's been in all night. It soon becomes clear that he is the only person that could have driven the car, as he matches the description – and the car has clearly been driven recently. Unfortunately, while he picked up the bumper of the car he hit, he managed to leave his own rear bumper behind. And yes, he was over the limit.
We join Taff and Chris, out in one of the STs on the M5 preparing to carry out a rolling stop of a car which is, apparently, carrying drugs. Despite it being dark and on an unlit road, this is one of their specialities, and they pull off the stop with aplomb, shocking the hell out of the occupants. There's a strong whiff of alcohol, but this turns out to be down to the passenger, enjoying a leisurely tinny or two as they go. The passenger admits to having some cannabis, but the driver claims to have only had the car for a week. The first objective is the delightful prospect of a strip search for the passenger, the next is to check if the driver is telling the truth about his car ownership. Which he is.
Chris is back with Mike, and in one of the Beemers, perched over the M5, when they are amazed to get an ANPR ding on a private paramedic ambulance which shows no insurance. Further enquiries reveal that the MOT is also expired, so they pull it. The guy that Chris speaks to turns out to be responsible for the fleet his company operates. He seems to have been more focused on his technician skills than his vehicles as the ambulance isn't even registered in his name, as he hasn't sent off the logbook to transfer ownership from the previous owner to himself. Chris and Mike have no option other than to seize the vehicle, Chris drives it to the nearest services so that they can sort out the paperwork before giving the Technician a bit of a talking to, threatening to take the whole fleet off if he doesn't get the paperwork sorted out.
Roger and Giles are behind a driver who isn't wearing his seatbelt. Giles talks to the driver while Roger takes on the task of dipping the tank for red diesel. He is stumped by what he finds, as it's neither clear nor red – as it's what Roger describes as a 'funny colour'. As Roger is the Detective rather than the Traffic Cop, he calls Giles over, who is rendered speechless by the liquid – which is black. As he's stumped, he attempts to find out what the driver is using, and is told that the driver mixes used engine oil with diesel. Never having come across this practice before, Giles contacts Customs to find out if they know what it's all about as it's impossible to to tell what colour the fuel actually is. And so he learns something new – that people aren't above sticking a bit of engine oil into their red diesel so that inconvenient dips such as the one Roger's just done fail to reveal that the fuel's illegal. While waiting for Customs to ring him back, Giles puts it to the driver that this is what he's done. Finally, they call back, and ask Giles to seize the car so that the fuel can be tested. This means that the driver has no transport beyond Collumpton nick – apart from the salvation of a bus service which Roger suddenly remembers. Results, when they're in reveal a mixture of red diesel, kerosene and engine oil. Bleagh.
Taff and Mark are out on the M5 near Tiverton in one of the STs and get a warning that a car with no insurance is nearby. When they find it, Mark gets Taff to put on the blues to pull it. Unfortunately, their target vehicle doesn't notice – but another driver does and thinks it's him they want. Next they try the siren, with no better effect. Eventually they discover the problem. Taff's only put the back lights on. From the front, their car looks like any old Ford Focus, with a driver doing semaphore. This time, they put on the front lights, and it finally does the trick. The driver claims his policy allows him to drive any car, but unfortunately, as the car itself isn't insured, this means that his own insurance doesn't cover him after all. It's a genuine mistake, which catches out lots of legit drivers every year, and Mark fully understands – but he still has to hand out the ticket and the points. He does, however, allow the driver to arrange insurance at the roadside, so he gets to keep the car. Taff dispenses some suitable advice to the camera, with some spanking alliteration and a cheerful swipe at his crewmate.
