"I won't say we went as far as having to take LSD, but... There were a couple of guys who were willing and volunteered."

Hi, I’m Crystal, a Senior Editor based in Los Angeles and creator of BuzzFeed’s “That Got Dark” newsletter.

And at a recent press event, I got the chance to speak with producer Rae Sanchini, stars Oona Chaplin and Stephen Lang, and three-time Oscar-winning VFX supervisor Richard Baneham about some of the behind-the-scenes details you’ll actually see in that footage...along with a few things you might not. Here's what I learned: