Automatic vehicles are introduced into the country. At first, things are great. Drivetime radio becomes highly intellectual, children take to the roads and the driving test becomes dead, dead easy. Only Jeremy Clarkson has his doubts, which he expresses by feeding a driverless car to a bear, live on Top Gear. And he's right. Soon the cars gain sentience, reproduce and use roundabouts as giant nests. Then, they take over the world.