“Avatar: The Way of the Water” by James Cameron is currently breaking box office records (as of this writing, it’s already the seventh-highest-grossing film of all time) and it’s a visual feast unlike anything that’s come before it.

But more dazzling than any special effect is the film’s emotional focus, provided in large part by the performances of Zoe Saldaña and Sam Worthington, who raise their children on Pandora and try to protect them from outside threats (like the villainous RDA ). They end up moving the family to another part of the planet and fall in with the Reef People, a band of mostly underwater Na’vi. It’s a simple enough story, but the emotional weight provided by their performances (and the genuinely heartbreaking storylines Cameron puts them in) makes the film something entirely different.

TheWrap spoke to Saldaña and Worthington about how their experiences as parents influenced their performance, how long ago Cameron started discussing sequels, and whether or not they regretted signing on for so many.

When did James start talking to you about a sequel or sequels?

Zoe Saldana: I think when we were shooting the first “Avatar”. It was more like, “When I grow up, I’ll do this,” that kind of essence, which was quite endearing. It’s like, “Well, if this movie does well and we prove this concept, I have so many ideas for what we’re going to do at Pandora.” And it was very promising. Never in a million years could we have imagined the reception “Avatar” would have. So in 2013, I think at the premiere or during awards season, Jim said, “Oh yeah, we’re totally going to go back.” And it wasn’t until 2013 that he told us. He contacted us all individually and said-

Sam Worthington: He figured out how to extend it.

Zoe Saldana: “I started to write.”

Sam Worthington: Yeah. He said, “Rather than make a carbon copy, I figured out how to expand the planet, expand the family.” And that was about as clear as it got. And then in 2015, we both went to see a room full of visuals from the saga. And I think my wife was very pregnant at the time, and we see a film in this form of drawing a family, and we think we’re about to take this trip. And it was like… It wasn’t cut into movies. It was just this really moving journey through images at that time. And then you go, “Well, how are we going to do this?”

You both had kids since the last movie…

Zoe Saldana: Oh, we have a football team. We have three boys each.

Sam Worthington: Yeah, it was not a prerequisite.

But did this life experience influence your performance?

Sam Worthington: Well, you’re going to have parental instincts anyway, and you’re going to have feelings of protection and feelings of…

Zoe Saldana: Fear. When you are young, you are not afraid of anything. You just don’t think about the consequences, and you’re in such a present mode. And any challenge, especially if someone like James Cameron comes to you, is like, “Climb that wall.” Of course, bring it. Look at me. Look at this. And then you have children, and you care about their lives more than your own. So any hypothetical scenario that could threaten the very source of your happiness and your purpose is unimaginable. They are that. The Sullys are so relatable. Jake and Neytiri are so close.

It’s obviously a massive film and in many ways more expansive than the original but with a much more intimate emotional focus.

Zoe Saldana: Yeah. We were arrested.

Sam Worthington: Protecting his family, but also the family that one chooses, that the young boy befriends an outcast, Tulkun, or armored whale. And that in itself is a very emotional bond that they create. So it’s all about protecting everything you love. And when you feel displaced, when you feel left out, when you feel the worst, all you really have are the people close to you that you can stick together with.

Where are you two in your “Avatar” saga? Should you be in New Zealand right now to shoot something?

Sam Worthington: They probably still go there. It was weird because, yeah, it wasn’t like there was a 10-year break. We were still doing stuff earlier in the year for performance capture, and Jim only locked down on Friday, I think.

Yes, he said five days ago was the first time he saw it finished.

Sam Worthington: That’s it. It’s a labor of love for Jim, that’s what it is. He doesn’t see it as “I’m going to make a movie”. He puts everything there. He’s the kind of guy you want to go make movies with.

Were you afraid to sign for so many sequels at once?

Sam Worthington: No, it’s Jim, man. Why would you-

Zoe Saldana: No. He could have said 60 films, and I would have said, “It’s done. Where is the pen in the paper and I will sign here. Does.”

Sam Worthington: You want to work with a collaborator who respects everyone. Whether you’ve never made a movie or Kate Winslet is an icon. You want someone who can push through all of these people and lead by example. The guy took up the hobby of free diving. It wasn’t just something he asked us to do. He had already conquered it before asking us to do so.

“Avatar: The Way of the Water” is in theaters now.