a man on a motorcycle does a backflip

and then knocks The Rock's character over.

But look behind the scenes

and you'll see nobody was injured that day,

because this shot was actually two separate takes.

This is a stunt trick known as a camera lock-off.

And it's just one of many tried-and-true techniques

Hollywood uses in films and TV shows,

making even the most unimaginable stunts come to life.

In this scene in "Baby Driver,"

Ansel Elgort's character pulls into a parking spot

and then runs out moments later.

In reality, that's a stunt driver driving into the spot.

The driver's side gets covered by this pillar,

which is also hiding Elgort.

So as Elgort runs out, it looks like

he's the one getting out of the car in the first place.

This is a trick known as a Texas switch,

an in-camera effect in which the actor and their double

will actually switch places midway through the action.

The move involves close collaboration

between the stunt crew, camera crew, and director.

Whether it's a whip off of the actual actor

to something to come right back to them,

you can't just go focused on that person

and then put another person in.

Narrator: And the set needs a natural hiding place

for the switch to occur,

like this rock that Sean Connery is hiding behind

in "From Russia With Love."

The Texas switch isn't just for action.

It's even become a comedic staple,

in everything from "The Naked Gun"...

to "Scott Pilgrim vs. the World."

Knives Chau: Is Scott here?

Oh, you know what?

[glass shattering] He just left.

Narrator: In this scene in "Elf," for example,

Buddy needs to put a star

on top of a very tall Christmas tree.

First, Will Ferrell runs off camera.

Then the double runs out

and launches himself on top of the tree.

[tree crashing]

"Maleficent: Mistress of Evil" contained many moments

where Angelina Jolie had to perform dialogue in midair.

So how exactly did they make it look like she was flying

while allowing for her to comfortably

and safely act in the scene?

They used this device, called a tuning fork,

which consists of two prongs that lock into

both sides of the performer's body.

The rig is controlled by a steering wheel

that is driven by stuntpeople in blue or green suits

who are erased in postproduction.

Tuning forks were especially useful

for the shots where Maleficent hovers in the air,

and the steering wheel makes 360-degree turns possible.

This was key for scenes where the Fey twist

and turn in the air in "Maleficent,"

or when Mulan performs full spins in the air

in the live-action remake.

You can also see it in action in "Captain Marvel"

when Carol Danvers realizes her full potential.

But the fork isn't a complete replacement for wires,

which are still crucial for flight.

According to stunt coordinator Monique Ganderton,

wirework helped give the character more mobility

in "Captain Marvel" and "Endgame."

She had two wires on her hips only,

'cause I like them to have freedom in their upper body.

And then a guy in a blue suit behind

just kind of puppeteer the leg up,

so her body could go side to side

and then come back up into an upright position.

Narrator: In "Men in Black: International,"

a menacing alien tosses Agent H down a staircase.

To achieve this violent-looking motion,

filmmakers use a trick called a ratchet pull.

During a ratchet pull, a performer is tied

to cables powered by an air-pressure cylinder,

which pulls them either backwards, forwards, or upwards.

The more pressure you use, the farther they'll go.

In "Twilight: Eclipse," for example,

Monique Ganderton was ratcheted 20 feet forward

after a CG wolf attacked her character.

Sometimes a simplified version of a ratchet pull

called a dead man will do.

Instead of tying a performer

to a complex rigging system off camera,

the performer is tied to

a solid, stationary object in-frame.

Monique: What happens is, when you fully commit,

you run, and you jump,

and you hit the end of that line,

and it just whips you back onto the ground.

Narrator: You can see it performed

during the battle of Wakanda in "Infinity War."

Monique: It gives for this violent,

this really simple but violent action.

Narrator: The dead man can also be used

to pull somebody off a horse,

like you see here in this cut sequence from "Chaos Walking."

And when Thor gets hit by Thanos in "Endgame,"

both a traditional ratchet pull

and a dead man were actually needed

so Chris Hemsworth's double, Bobby Holland Hanton,

could be pulled forward and then thrown to the ground.

Getting a stunt performer to go through glass,

like in this scene from "The Hunt,"

requires a lot more force than just a person's body weight.

When a character needs to jump or fall out a window,

productions use tempered glass,

which shatters into tiny, harmless bits

instead of sharp shards.

But the glass itself is so strong

actors would simply bounce off it,

as you can see in this gag.

So in these moments, the special effects team

rigs the glass with explosives timed to go off

the exact moment the performer falls through.

Daniel: By cracking it, you weaken the whole system.

Narrator: In "The Hunt," the doubles

were attached to a wire that pulled them backwards

just as the explosives go off.

Exploding glass also helped hoist stuntman Daniel Hargrave

out a window in "The Accountant."

If you look on the ground, you can see how tiny

the broken glass pieces actually are.

Stuntpeople are finding efficient ways

to update this trick too.

In "John Wick 2," the character

is thrown through a glass sculpture.

Daniel: Basically the performers had to hit the glass

and let the computerized system do its thing.

They put four charges that were pressurized into the glass,

so it was on a pressure system.

As soon as that glass pushed against the charger,

it had, like, maybe a eighth of an inch of pressure on it,

so as soon as you'd push through, it would blow.

[glass shattering]

Narrator: This risky stunk from "Central Intelligence,"

in which The Rock's Bob Stone is hit in the head

by a motorcycle, was made possible

by clever camerawork and visual effects.

In a trick known as a camera lock-off,

two actions are shot separately from a camera

that is locked into the exact same place both times.

Then those two shots are combined using visual effects.

First, filmmakers shot a motorcyclist doing a backflip.

Then, in another shot from the same angle,

stunt double Tanoai Reed was pulled back

on a ratchet to imitate impact.

The wires were erased and the two shots layered together

into a seamless whole.

For moments like this,

stuntpeople can actually get hit by cars.

But lock-offs can lessen the pain of vehicular hits.

Take this moment in "Atomic Blonde,"

where Gascoigne, played by Sam Hargrave,

is hit by a car and then smashed into a van in front of him.

Daniel: Sam was on a ratchet,

so he ran to his mark, and we ratcheted him into the van.

So no car hit him.

And then I was driving the car, and we just,

same thing, lock-off, I slid in as if I hit him,

and then they merged together.

And then he just turns, and you see a wide shot of him

getting hit and flipped into this car.

[grunts]

Narrator: In "Underworld," the werewolf Lucian

has to run at superhuman speed.

And this isn't the work of CGI or camera tricks.

It's actually a practical effect called a magic carpet.

For this stunt, the crew will attach

a large tarp to a vehicle.

The performer will start running on the smooth surface

as the car drives, allowing them to run much faster

than a normal human would.

"Underworld" stunt coordinator Brad Martin

had actor Michael Sheen and his stunt double

run on an 80-foot tarp attached to a car,

creating the appearance of running at 35 miles per hour.

It was so successful that Martin

used it again in "Underworld: Awakening."

It can make just about any type of character

look like they have superhuman speed.

Without a magic carpet,

the actors in 2001's "Planet of the Apes"

would never look as fast as apes on all fours.

And it's also why Black Panther looks so fast

when he runs and jumps onto the back of a car

in "Captain America: Civil War."

However, this really only works

on flat surfaces like asphalt.

For off-road terrain, stunt crews may use

a weighted wire system attached to a winch,

basically a giant spool,

to physically lift and propel them.

Look at the start of the battle of Wakanda

in "Avengers: Infinity War"

when Captain America sprints past his fellow Avengers,

who are also running at full speed.

Stunt double Daniel Hargrave was clipped into a harness

and attached to wires above his head.

The winch was then weighted to counteract his body weight,

helping him move up and forward.

With the extra help, he could run up to 24 miles per hour.

Daniel: I was about 50% on my feet,

so I still had to run and move my feet as fast as possible,

but I wasn't actually doing all the propelling myself.

Narrator: And it's helpful with Marvel villains as well.

In "The Incredible Hulk," a similar weighted system

helped Emil outrun several soldiers

after taking the superserum,

launching actor Tim Roth to speeds

ranging from 30 to 40 miles per hour.

Some of Hollywood's most daring car stunts

need trained stunt drivers to pull them off safely.

But what if you still want to make it appear

as if the actor is the one driving?

A much more dynamic way to capture chases

is by using a Biscuit.

It's a vehicle that you can put other vehicles on.

So while the actors appear to be driving on camera,

the real work is being done by a stunt driver

sitting in a driver's pod just out of frame.

But because the stunt driver isn't seen in a Biscuit rig,

the camera can capture way more dynamic angles.

These rigs allowed the audience to see Christian Bale

up close in "Ford v Ferrari,"

and some seemingly impossible car moves in "Baby Driver."

In the movie "Drive," they actually shot this part twice,

where Ryan Gosling's character gets hit by another car.

First they shot the exteriors

with two actual stunt drivers,

then they shot Gosling on the Biscuit,

able to mimic every move to get the inside of the car.

Director: And ready, and action.

Narrator: CGI can be used to create big, safe fires.

But fire is still one of the hardest elements

to create with visual effects.

It's easier to set a real stuntperson ablaze.

So, how do they do it without causing any harm?

Stunt performers often wear three layers

of fireproof underwear, which is soaked

in a flame-retardant material called Zel Jel.