So we're near the end of the movie.

And this is the culminating, the final fight scene

between the women and the gangs

that Roman Sionis, played by Ewan McGregor,

sends in to the funhouse, which

is called the Booby Trap.

Well, originally, it wasn't a funhouse, actually.

I believe, originally, it was a hotel.

And they were supposed to fight their way down.

But then, when I got together with our amazing production

designer, KK Barrett, and our DP, Matthew Libatique,

we kind of thought, wouldn't it

be more interesting to convey a location that

felt like Harley Quinn's mind on acid?

Our actresses, they're actually

doing the majority of the stunts themselves.

That was four to five months of brutal training.

When we were in prep, the actors

were training pretty much every day

with our stunt team."

"Come on!"

"Margot learned to roller skate for this movie

because she ends up roller skating in a good portion

of the movie.

She learned to roller skate on a bank track

for the derby scene.

And then, obviously, she's roller skating here.

And for this moment, she is actually just roller skating.

And she was so--

she became so good that she was

able to stop herself, which is actually

the most difficult thing to do,

while on a rotating carousel, which

is infinitely harder than when you're not

on a rotating carousel.

What was another big challenge that we only sort of realized

on the day, too, was that because the background was

so different, for continuity, whenever we started a take,

we had to make sure that we started and ended

at the same point.

So the carousel became a sort of clock.

And we had a number for each of the hands.

And then each hand had to directly correlate

with a point outside in the funhouse

so that we were able to actually match up

the backgrounds.

If we didn't do that, then it would have

been a complete nightmare."

[MUSIC PLAYING]

"[SHOUTS] Ah.

Wait."