From filmmaker James Cameron, the sci-fi action adventure sequel Avatar: The Way of Water is set more than a decade after the events of the first film and follows Jake Sully (Sam Worthington) and Neytiri (Zoe Saldaña), as they do whatever it takes to protect their family. With a familiar danger threatening everything they hold dear, they journey to the water world where they must learn to adapt to new customs and traditions while an epic and unavoidable battle is looming.

During a press conference to promote the highly anticipated film, Worthington, Saldaña and Cameron talked about why it wasn’t a given that they’d return to this world, figuring out what the sequel would be, the progression of the characters, figuring out how to bring the character of Grace (Sigourney Weaver) back, and what Cameron is most proud of with this accomplishment.

Question: Jim, what was the moment that you knew you would be returning to this world?

JAMES CAMERON: That’s an interesting question because it seems obvious to everyone going, “Oh, you just made a bunch of money, so do a sequel.” Steven Spielberg didn’t do a sequel to E.T., the highest grossing film in its time. It’s not a no-brainer. Do you wanna call down the lightning strike again, in the same spot? It’s a lot to live up to.

But you know, we have this amazing cast. We have an amazing cast that returned, and we figured out a way to bring [Sigourney Weaver] back, even though her character from the first film died. We also had this amazing family of artists and troupe players, and all the other actors. When you see a crowd scene in this movie, of a hundred people, it’s the same ten actors just moved around. It’s a small group, and we love each other and enjoy the process. That was a big incentive for me, to come back and do this all again.

Image via 20th Century Studios

Did you know right away where you wanted to take the story and characters?

CAMERON: It’s important for a sequel to honor what the audience loved about the experience the first time, but also to get them off-balance by doing things that they don’t expect. There are a lot of surprises, in terms of where the story goes in this film, that we’re not putting into the trailers and the TV spots. You have to experience it. It goes a lot deeper, in terms of the heart and the emotions. It was a much simpler story and the characters were simpler, the first time. I was inspired by the fact that both Zoe [Saldaña] and Sam [Worthington] are parents, and I’m a parent of five. We wanted to get into the family dynamics and the responsibilities of having kids, along with what that’s like from the kid’s perspective.

Zoe and Sam, what can you say about where your characters are at in this film, and what it was like for you to return to these roles?

SAM WORTHINGTON: Jim gave me a script that was Avatar 1.5, that was amazing and detailed and full of what they’d gone through, over that gap. Jim realized that story was about them being warriors and taking on the battles of the clans. He wanted to explore what this family dynamic is and the natural extension of this love story. It gave us a good jumping-off point, to understand how to fill in that gap that’s missing. It was pretty amazing.

ZOE SALDAÑA: When something is very similar to you, you can’t see it. It’s so close to you that it’s not in front of you. And Neytiri and I, in a way, have lived parallel lives. There’s a level of fearlessness and rebellion that I have, as a person, that Neytiri has, herself, and I was able to find kindred in that. The leap of falling in love with something outside of you, that challenges you to see something that you’ve never seen before, has always been her dilemma. To surrender to that, and then to bring forward the fruits of that love presents a challenge for her. Forcing her to grow is forcing her to love something that she’s been taught to hate. It’s really, really hard. Also, In my personal life, when I became a parent, fear entered my realm, with the fear of losing something that you love so much. You spend a great deal of your time creating these hypothetical scenarios that are just unimaginable. When I read the second script, that was Neytiri, but I didn’t see it then. I see it now. My job wasn’t to see it. My job was to be it.

CAMERON: You may be fearless when you don’t have kids. You learn fear when you have kids because you have something greater than yourself that you could lose. That’s what both of their characters are dealing with. Sam plays a character that would leap off of a leonopteryx and go flying through the air with no parachute, to land on the biggest, meanest predator on the planet, in order to solve his problem. Would he do that as a father of four? I’m thinking probably not.

Image via 20th Century Studios

Jim, what was your process for deciding how to bring Grace (Sigourney Weaver) back?

CAMERON: Grace’s avatar was still alive. It has no mind of its own because it needed to be infused with Grace’s consciousness, in order to move around and talk, but she turned out to be pregnant and a vessel for this little baby. That’s Jake’s problem and Neytiri’s problem, so she becomes the adoptive daughter. Jake had a mother/son relationship with Grace, in the first film. She took him under her wing, so he’s gonna protect her child and raise her child as his own. She’s the daughter, but she’s also a bit strange. There’s something unknown and enigmatic about her.

Sig walked a beautiful line of classic teenage awkwardness, and yet as she comes into her power and strength, she’s not a warrior. She’s not somebody who would react in a situation like Neytiri would. She’ll react very differently. She’s not really that much of an alpha, until we see her manifesting her power. So, I thought we had the opportunity to speak to teenage girls, in a way that might make sense to them. I was very well aware of this problem. I read Reviving Ophelia. I have daughters of my own. I’ve seen them go through it. I’ve seen their confusion over wondering, “Who am I? Who’s listening to me?” All the things you go through when you’re a teen, I had researched that for Titanic, and then I’d lived it, as a father, after that. There are different ways for a female to be strong. When your kids are in jeopardy, you’re on the move, and it’s instantaneous.

It’s been 13 years since the release of Avatar. Zoe, how have you changed, as an actor, and did your character change in the same way?

SALDAÑA: I don’t know how I’ve changed, as an actor. There’s certainly a level of presence that I have today, that I had once before, and somewhere in the middle, that got muddled. I’m happy to reconnect with that. I think it’s just about fear. Fear was a sensation that was paralyzing to me. It still is sometimes. And now that I’m living in it, having been a mother for eight years, I’m learning to manage that sensation enough to let go. There’s nothing greater and more heart-breaking than when your child looks at you and goes, “Momma, let me go. I can do this.” That’s what the Sullies are telling Jake and Neytiri, all the time. Fearlessness and fear are two very humbling sensations to experience, for sure.

Image via 20th Century Studios

Sam, has Jake found a new journey in love and fatherhood?

WORTHINGTON: In the first one, he says it in the voice-over, “Open your eyes.” He’s opened his eyes to love – the love of culture, the love of the planet, and the love of Neytiri. In this one, it’s the natural extension of that. They have a family and, to be honest, it’s about the protection of that love, that world, and that culture.

I always saw it as the simplest form. His partner in crime is a very fiery person. He tries to be the earth, and we just happen to have a lot of water. It’s very elemental. It’s very base. Jake’s journey has always had these parallels of, where does he fit into this world? Can he find something worth fighting for? Teenage boys are displaced and, like most teenagers, they’re trying to figure out where they fit in the world, and Jake is the perfect person to help them. Sometimes, as a dad, you can’t find that empathy, or you’re learning to find that empathy, and he’s trying to help these boys. I actually think he relates more with Kiri. Jake is a warrior, but sometimes you have to become a bit of a pacifist and calm down, in order to listen to your kids. I’ve learned that. That’s how he can connect with someone like Kiri.

Jim, what was your biggest source of pride or proudest moment while filming this sequel?

CAMERON: Everybody’s mighty in this film, in their own ways. I watched the film with the visual effects unfinished once, six months ago, not in 3D, and then I watched it again a week ago for the first time, because I try to do that very sparingly. I work on the minutia all day long, 10 or 11 hours a day, but I rarely stand back and see the whole thing. And what struck me was the work, the performances, and the people. I look past all the spectacle, all the design, all the creatures and all that. I’m not only proud of the work, because you’ve got to start with that, but I’m also proud of the entire downstream team of over a thousand people, who preserved it so eloquently and so subtly. When we’re in the capture space, we have the ability to be as detailed and specific as we want to be. If you’re just being generic, that’s not the kind of challenge that we want. At this stage in our lives and our careers, we want a challenge. We want to find just the right timbre for every moment. If you can’t trust the downstream process, that it’s going to come through in the CG characters, then what’s the point? I’m very proud, not only of what we created together, but how that was preserved into these fantasy characters that are not human, and that are very physiologically different from humans.

Avatar: The Way of Water is in theaters on December 16th. For more on the making of the film, check out Collider’s interview with Cameron below: