Dark Phoenix is many things, but at its core it's the story of Sophie Turner's Jean Grey, who gains immense power that alienates her from the X-Men and those closest to her - and right towards Jessica Chastain's mysterious alien presence. The two actors spend much of the movie together, where the main power play unfolds.

Screen Rant recently sat down with the Dark Phoenix stars to discuss developing their characters and working with writer-director Simon Kinberg.

This is obviously one of the biggest, if not the biggest, X-Men story in the comics. Did you guys go back and read The Dark Phoenix Saga in preparation and pull from that?

Sophie Turner: Well. I'd read it years ago and then I read it again when I got Apocalypse and then, no.

Jessica Chastain: Yeah, for me, my character doesn't appear in it, so there wasn't any sense of me going and finding source material that didn't include my character in terms of research.

Jessica, your character is a very obscure comic character that pulls from various different threads. For that, did you lean more on what Simon has written for the script rather than the comics, then?

JC: Absolutely. And then also, a lot of Google searches about, you know, different alien species in that world.

Sophie, you mentioned Apocalypse. When you signed on for that, was this always part of the pitch? Did you know you'd get to do the good stuff?

ST: No, not at all. I never knew. You know, they had The Last Stand and so I just kind of assumed that it was done and over with. But I was really excited when they told me because in The Last Stand, the Dark Phoenix storyline was a subplot and in this it's the main plot and it being one of the most loved comic books in the X-Men world, it definitely felt right to do it again. I was so excited.

Jessica Chastain and Sophie Turner in X-Men Dark Phoenix

And what's so exciting about this one is that Simon is writing and directing. So you have a very driven direction which you don't always get on movies of this scale. How was that for both of you working with him and being able to shape this central relationship in the story?

JC: It's great. I mean, I love working with writer-directors because you could have a conversation and something comes from that and then the next morning, Simon would show up to work and say, "hey, I wrote some pages that I think could be interesting for this direction we're going." So I love that kind of, you

know, that fluid way of working.

ST: Yeah, it's just like you're constantly evolving. The script is constantly evolving and being chopped and changed in whatever way kind of way we liked,  and that was amazing. He's so collaborative, that was something that is often quite rare in directors, and he was great.

Could you elaborate a bit on that? In terms of the collaboration, what were you able to introduce to the character that perhaps wasn't in the script? Both of them, of course.

ST: It was probably just little things, you know. Like, Simon and I would sit down for two hours every day and just comb through each page of the script. And then, if I felt like, "oh, Scott and Jean need to have a moment here because this happens later on and it would make sense," he would be like, "yeah, no problem." And he'd rewrite it. I mean, there was rewriting being done all the time.

JC: For me, I mean, the look of the character was something that I brought to Simon and we worked together to hone in. And then things about the clinical nature of her, this idea that she wouldn't be very emotional because when I read the script I was like, it's a very emotional script, so I think it's nice to have a character who sees that as weakness and is giving another kind of performance for that to go off of.

Next: Simon Kinberg Interview: Dark Phoenix

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