Whether it’s a superhero movie, a bank heist flick or a tense spy thriller, there’s a good chance the film you watch this weekend will show the gruesome destruction of at least a couple of cars. But what most of us don’t know is the lengths Hollywood and the TV studios go to to make sure those vehicles get damaged in exactly the way the directors want.

A new video on Insider’s YouTube channel covers some of those methods with the help of JEM FX, one of the companies Hollywood has called on for help making movies like Shang-Chi and the Legend of the Ten Rings.

If you’ve seen the Ten Rings movie you might remember the scene where a runaway bus in San Francisco drives over the top of a bunch of cars including a BMW i8 and Porsche 944, completely flattening the roof of each. But we all know from seeing real crashed cars that a car roof and pillars are pretty strong, so to get the “crushed” look the movie’s producers were looking for from the cars JEM cut sections out of their screen pillars. The modifications were invisible from the outside, but allowed the roof of each vehicle to compress instantly and completely when the bus climbed over the top.

Related: Why Do Movie Studios Destroy So Many Valuable Cars? The Secret Is They Don’t

Other tricks include fitting cars with fake panels fashioned from soft aluminum that can crumple on demand, either when hit, or by being pulled from the other side of the panel by a device hidden from the camera. This technique was used in Ghostbusters: Afterlife when the production team needed a truck’s bodywork to look like it had been dented during a chase by a ghost that would be added using CGI technology later.

JEM also reveals how it partially cuts hoods and then fits them with rams so the hood can crunch up in front of the windshield when the car hits a wall or another car, and even how it welded giant wheels onto the side of a shipping container to make it look like it was tumbling down a road.

You might argue that knowing some of these movie hacks spoils the magic a little, but if you’re like us and enjoy discovering what goes into making stunt sequences happen as much as you like seeing the end result, this video is definitely worth watching.