A toddler gets locked inside a car with the key inside. Frantic onlookers try to indicate to him by gestures what he should do to unlock the door, so that they did not have to do something extreme like breaking a window which might have hurt the child with the shattered glass.
I know that it used to be the case that police and car mechanics carried with them a thin metal strip that they could insert down the door window and pull a lever to release the lock. But it may be that newer cars with their better security systems have closed that option. Even two decades ago, I was with a friend who had locked her car with the key inside. The police and the mechanics who were called could not get it unlocked using the metal strip because they said it was a Mercedes and thus had a more secure system. Like most things, such features have likely migrated down to the lower end of cars.
I always carry a spare key. Car owners are given three keys, two regular and one valet key. I always keep one car key by itself on a separate ring that is the one I use and a duplicate on a different ring with my other keys, so I always have a spare. I started doing this after a friend of mine was robbed in a parking lot by someone who demanded his car keys. Since it was on the same ring as all his other keys, he lost the lot and as a result had to change his house locks as well, which was a real pain. Now if I should get mugged by someone who wants my car, I will lose only that.