Well, he can jump out.
4 seconds sound clip from the Rain Man (1988) movie soundboard.
You can hear this line at 00:18:52 in the Blu-ray version of the movie.
Quote context
[...]
- Look, my boyfriend is coming.
- Course, today's Monday. I always drive the car on Saturday, never drive on Monday.
- What is this? Who is this guy?
- I don't know, he jumped into the car.
- That's good. Come on, come on.
- Why did you let him get in this car? It's not a toy.
[...]