The filmmakers were granted unprecedented access to shoot in the actual catacombs, including some of its restricted sections.

Tell me, what was the genesis for the creation of this story?

We were done with that subgenre unless we did a found footage that was a female Indiana Jones character.

What would that be like?

Something epic, but done on a really intimate scale.

So, we had that idea sort of kicking around, but we were focused on other stuff.

Weve long been fascinated with the catacombs but we had never put the two together.

He brought up the idea, Guys, Id love to do something in the Parisian catacombs.

Do you guys have any ideas?

It was just that lightning bolt moment.

We had all these ideas that sort of came together.

We pitched the idea two days later, and then we just started making it.

Things moved very quickly from that first meeting.

JD:It was pretty crazy.

We kind of have a … were very safety conscious.

We have all kinds of rules and tricks.

But in those confined spaces, people would take headerstheyd hit their heads on the ceiling quite a bit.

That was actually a little dangerous.

One of our assistant camera guys got whiplash from hitting his head, and his head cranking back.

He had to wear a neck brace until the end of the shoot.

Shooting down there, we just had to take a really intelligent approach to shooting.

We had the actors…the scenes were lit by the actual actors headlamps.

We tried very hard never to set marks, never to force the actor into a specific blocking.

Actors could move wherever they wanted on any take.

And the camera could follow.

We kept it really facet-less, and shot it like you would shoot a real documentary.

We kept it really lively and fun.

Even if it was fiction and she used it, they would think people are stealing from her.

Were you worried about that, one way or the other?

Did you ever want to change it to somebody fictional?

JD:You know, no.

We wanted to go with stuff that was kind of a real legend.

He was a famous Romanian alchemist.

Just the fact, to capture that in a realistic kind of format, versus a fantasy.

DD:We liked the idea of a found footage movie in a supernatural space.

It really did have a real history to jump off, to go into that supernatural space.

We obviously knew the Harry Potter connection, but it never gave us a second of a pause.

It just is so different.

Its a real history.

Its not like were taking a fictional character from Harry Potter.

It never concerned us.

Your main cameraman really gets hurt first, which generally doesnt happen in found footage movies.

Was that something purposefully you were trying to do, new and different?

JD:A little of each.

We try very hard to do little things to keep the audience off-balance.

If the audience is off-balance, it forces them to pay attention.

When things happen by the numbers, they dont have to pay as close attentionits just not very enjoyable.

JD:Oh, yeah.

For a moment, I forgot that he was inCloverfield.

Thats a really hard thing to do.

I feel like there are certain actors that can throw away dialogue in a way thats very natural.

Bens really, really great at that.

Im sure thats what jumped out to us.

DD:Its a fine balance too between your relationship and the camera in a found footage movie.

If you cross that line too much, it becomes a little too present.

Its a tough balance.

JD:Its pretty great.

What if we do little jump cuts in it?

How would that look?

I hadnt really seen that in a normal narrative.

As a director, so rarely do you get to show up on set, warm.

Okay, Im really doing it now.

Whereas, when we shotAs Above, seven weeks [later] we were shootingThe Coup.

It was nice to show up to that set really warm, and really feeling in fighting shape.

DD:I got so used to the blocking, just setting up everyday.

Really take a found footage approach to blocking, and well deal with it in editorial, later.

The actors loved that, they really did.

We dont believe in taking breaks.

DD:Its usually unintended when were taking breaks.

So were hoping not to.

So, Ill let you go and have a one-minute break before the next person calls in.

Thats something, at least.

DD:Really nice to talk to you, Matthew.

Thank you, you too.

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