A favourite assassination method of mobsters and spies alike is to hook up a bomb to the ignition switch of a car, so that it will lie dormant until some poor soul starts it. While the intended target is, naturally, the car's owner, this trope is the number one killer of chauffeurs, valets and helpful Disposable Women - which occasionally raises the Fridge Logic of why you would put an ignition-triggered explosive in a chauffeured car in the first place... A subtrope of Vehicular Sabotage. See Every Car Is a Pinto for cars blowing up that have no reason to.