It occasionally happens, following a collision between a car and a pedestrian or in a deliberate assault with a motor vehicle, that the pedestrian comes to be caught or wedged beneath the car, and that the driver then travels on for a considerable distance, afterwards claiming to have been unaware of the presence of the person. In such incidents, investigators are often incredulous that the driver should not have been able to “feel” that there was something underneath his car, and that he did not stop at least to find out what the problem was. The only practical way of investigating the matter further is to carry out practical tests with a suitable car and dummy. This paper describes the tests performed by the authors following one such incident, and begins with accounts of two previous incidents investigated in a more subjective fashion. The general conclusion is that the effect on the behavior of the car is very small and that a driver might indeed be unaware that there was a person trapped beneath them.