By Helen O'Hara | Posted 8 Dec 2017

The first trailer for Alita: Battle Angel sets out the stall for the film: both faithful to the look of the manga’s big-eyed heroine and ready to adapt both story and characters to the modern day. Robert Rodriguez is the man who got it done when Avatar distracted James Cameron from the task (he wrote the script with Laeta Kalogridis and remains aboard as producer), and we called him up yesterday to get the lowdown on this first glimpse of the film.

On working with Cameron

This just doesn't happen. Guys like Quentin [Tarantino] and Jim [Cameron] only write scripts for themselves to direct. When Avatar becomes the biggest movie of all time, he told me that he's going to spend the rest of his career making Avatars, so I said, 'What happens to Battle Angel then?' - because as a fan I was just interested! And he said, 'I don't think I'll ever get to do that. Hey, if you can figure out the script, you can shoot it!' So I took it home, spent all summer working on it, cut it down to 130, 125 pages, without cutting anything that he missed. It was a great gift. We had a blast; anytime I had a question I could just call him or email him and he would send back these hugely detailed answers that were so helpful. He just loves being the producer that he always wants. The guy's just so freakin' smart. Getting to learn from someone like that was the greatest internship ever.

Alita (Rosa Salazar)

That's such an important character and you start wondering, can we find the right person to play this role? Who's gonna pop? A lot of terrific people came in, and then she showed up and... I'd never cried before in an audition. That was embarrassing! I thought, ‘Lemme watch the tapes,’ because sometimes when you see somebody in a room it doesn't translate to the screen, and the other way around. Sure enough, it was on the tape too; I cried again. I sent it to Jim [Cameron] and said, 'Hey, I don't wanna jump the gun but this girl is really amazing, and it at least shows that we can find somebody'. And he said, 'I don't think we even need to look any further. This is the girl'. We kept looking for another month or two, did our due diligence, proper screentests and everything, and it just clarified that she was really special and that's the character.

The eyes

It was always Jim's intention to create a photo-realistic version of the manga eyes that we're so accustomed to seeing. We really wanted to honour that tradition and see that look standing next to any human character. To have the right person to emote behind it was really essential. Her origins are in the film and you understand why she looks that way. If the eyes are the windows to the soul, we have some pretty big windows. You can see a lot going on in there! When it gets to the emotional scenes it's really uncanny and striking. And captivating!

The arms

When you see the movie you'll understand the story behind it [the scrollwork on her arms] but it's one of those things. It was another thing that took my breath away in Jim's early art. There was the scrollwork that a father would create for his daughter, on her body to replace another body. It's all meticulous detail and clockwork design. When you're filming it, it looks like a grey sock because it's a capture suit, but I'm thinking to the future going, OK, a year and a half from now when the effects are done it's probably going to be really striking so I'm going to get really close to this sock and hope!

Iron City

The Scrapyard where Ido finds Alita is in Iron City. [The city in the sky] was Tapheris in the manga and I think Zalem in the anime. That's what we're calling it in the movie. It’s Weta doing the effects. They just do the best work. I've never gotten to work with a company like that before. So much great stuff comes in from Weta every day that every day is Christmas. You're seeing the movie slowly come to life and you're like, 'Wow, that's amazing!'

Dyson Ido (Christoph Waltz)

Ido is the one who finds her in the Scrapheap and becomes this father figure to her and mentor, because he's a hunter-warrior as well as a doctor. In Iron City, there's no cops so citizens have to go do the dirty work themselves of cleaning up the town. You'll find out in the movie why he takes that on. Christoph’s just so frigging good! Him just holding the body in that shot, you get the connection - and when you see the movie you'll understand what it means to him to hold that body up, and the history that goes with it. Nurse Gerhad (Idara Victor) is an assistant to Ido. She has a mechanical hand that has all the fine tools that move around hypnotically.

Chiren (Jennifer Connelly)

Chiren’s from the anime version. Chiren is a mysterious character, I don't want to give too much away about who she is, but she has somewhat of a connection to the character of Alita. Jim’s thing is that the more fantastical the story, the more it has to be grounded in reality. So I thought, let's really cast these role up because it'll elevate the whole project. So Christoph, and Jennifer Connelly as Chiren and then Mahershala [Ali], who I'd worked with before on Predators, won an Oscar during the making of the movie, so we ended up with three Oscar winners in the cast!

Hugo (Keean Johnson)

He had to be a very young man, like 19, 20 years old. And he also has to have a level of maturity because you grow up fast in Iron City, you've gotta be very world-weary by 19, so finding somebody with that kind of street smarts, and someone where you would understand someone as cool as Alita falling in love with, that's a tall order. This kid kept coming in and there was something about him. We screen-tested him and he really just kept getting better and better every time he came in. He's a real find. I think it's his first big feature.

Vector / Nova (Mahershala Ali)

He plays Vector, who's famous from the manga [as a black-market dealer who Hugo works for] and then there's a villainous character called Nova who can, like, ride through other people. He can take over their bodies. So he has to play someone else; that was really fun. We got the actor to come in and do the main role he's playing, but then you kind of have to create a whole other character with him. I showed his footage to Jim and he was like, 'It's a totally different person!' Posture, voice, the look in their eye: it's a lot of fun for an actor to do that. One, to play the first character but then have to come up with a second character on top.

Zapan (Ed Skrein)

He was in a grey body sock and owned it. As you see in the trailer, the cyborg body comes all the way up his neck and into his head, so it has a make-up effect that makes his face look like it's floating. And you're walking around trying to badass in a grey sock and a flimsy grey plastic sword hanging from your belt, but he was just so comfortable! I kind of combined him with another character in Jim's script when I tried to condense it, so he has a really villainous turn. It actually becomes a much better role in the film than it was in the manga. So you see a bit of him stalking after one of the characters; he gets really deadly. He is formidable and snake-like, and Ed is so fun and terrific.

Grewishka (Jackie Earle Haley)

Grewishka is one of the main adversaries and Jackie is fantastic. He sent us an audition tape that was just awesome. He had the voice and the rage, and he doesn't have to be 9' tall, because we can make him that. He plays one of the biggest badasses in the movie, Jackie Earle Haley. And it looks like him! You don't see that much in the trailer, but even though we completely redesigned his head to look more like Grewishka, his face just cuts through, his performance is completely there. It looks like Jackie, but crazy big and strong.

Nyssiana (Eiza González)

I discovered her for From Dusk Till Dawn [the TV series] and she was in Baby Driver recently; she's wonderful. I told her, 'This part may not seem like a huge part when you read it, but trust me, you're going to be all visual effects. You're going to be wearing a [body] sock and you're going to look amazing! I think you're going to have a lot of fun with it.' I needed somebody who could act through the make-up and pull of prosthetics for that particular character and she just did it so well. She was perfect.