When you're driving, many unexpected things can happen. There are however certain situations you need to be extremely vary of.
The first goal of robbers/kidnappers is to get you to stop your vehicle and potentially leave it. The moment you do either of these things, your safety will drastically drop.
That's why if you encounter something such as person purposely aggravating you, you need to be especially vary. Something as simple as smacking an egg on the windshield can do wonders. Turning on the windshield wiper could potentially smear the entire windshield preventing the target from driving away. It's one method that'll almost certainly enrage the driver and cause some kind of reaction.
Another obvious red flag is if someone tries to signal you to pull over due to some arbitrary reason.
Robbers aren't stupid enough to play fair and they could resort to anything.