The review embargo on Marvel Studios‘ Ant-Man and the Wasp: Quantumania (dir. Peyton Reed) has been up for barely an hour and I’ve already seen someone describe Cassie Lang, played by Kathryn Newton, as an “arrogant wannabe activist”. I’m convinced that some of y’all just hate fun.
In the follow-up to 2018’s Ant-Man and the Wasp, Newton takes over playing the teenage version of Cassie in Quantumania, a job that has a lot riding on it: Cassie has always been Scott Lang’s (Paul Rudd) superpower, and their relationship is the heart and soul of this franchise.
Cassie began the Ant-Man trilogy as a precocious 8 year-old (originally played by Abby Ryder Fortson) who looked up to her dad, affectionately anointing him “World’s Best Grandma” in the second film. In Quantumania, she’s grown into someone who just can’t turn the other way when people need help — there were a few times in the film where I whisper-exclaimed, “Okay, Comrade Cassie!”
Newton has her own origin story with the MCU, having grown up watching the movies with her dad. As a kid watching the first Iron Man, she’d wished it were her up on the screen fighting, falling, and learning to pick herself back up again. One of the richest aspects of where we find ourselves in the post-Endgame setting of the MCU is witnessing a new generation of heroes rise to the occasion of defending the world from all sorts of threats, struggling to do good while figuring out their own lives in the process.
Without spoiling anything, one of the most magical things about Quantumania is the payoff of Cassie Lang’s arc. At last week’s premiere in Toronto, Off Colour spoke with Kathryn Newton about how hers and Cassie’s dreams came true. For Newton, it was portraying a larger-than-life superheroine. For Cassie, it was finally teaming up with her dad to save the world.
This interview has been edited for clarity, formatting, and length.

Cassie is a bit of a mess and she leads with her heart.
Off Colour: How was your birthday?
Kathryn Newton: Oh my gosh, my birthday (February 8) was the premiere day and then yesterday, I had so many balloons, and cake and flowers from Marvel and my cast. Jonathan (Majors) and Evangeline (Lilly) sang me happy birthday. It was amazing. It was amazing. You know, it’s been many-birthday-wishes-in-one to be in this movie.
What was your preparation for going into this role? What kind of comics did you read?
KN: I had a whole encyclopedia of Cassie Lang comics to look through. I got to discover a little bit of who she is and who she could be. But I really relied on the script, because this version of Cassie is not like anything you’ve ever seen. I’m so lucky that the fans have been introduced to Cassie Lang already, and they love her so much. We really wanted to carry that legacy and we didn’t think about it lightly. We really wanted to give her the best shot of being loved by the fandom. I did a lot of training too.
A lot of it was training to learn how to fall and take a punch. And because Cassie, as you will see in this movie, she wants to be a hero, but she doesn’t really know how. We were really similar in this was my first Marvel movie. I wanted everyone to love me and make everybody proud, and I think Cassie is the same way. She’s just trying to impress her dad, you know? But when I fall and stuff in this movie, that was not acting — it was me not being a professional Marvel superhero just yet.

What was it about Cassie as a character that you latched on to, what emotionally resonated with you?
KN: Well, I think that she really cares about people. My favourite thing about her is her heart. She leads with her heart and I resonate with that, but the biggest thing I resonate with is her impatience. I’m so impatient. I don’t think before I speak, which is why I spoil so many things. They’re calling me Tom Holland over here.
Not Tom Holland!
KN: I really don’t think I’m that bad. Like, I really don’t think I spoil anything.
I haven’t seen anything.
KN: I kinda did one time, but we’re just gonna let it go.
I don’t know what you’re talking about.
KN: Good! And so that’s basically the biggest thing is that she’s super impatient and kind of a mess, like tripping over herself. You know, when you’re like, body’s ahead of your brain.
That’s who she is. She doesn’t think too much. She just wants to help people, and I love that. It’s a beautiful thing. But it gets her into a lot of trouble, which is, you know, if you saw the trailer, you know, this is my fault.
I mean, she’s 18.
KN: But also? You’re welcome for Phase Five of the [MCU]. Like, Kang wouldn’t have happened without her. So you’re welcome!
Kathryn Newton hopes young kids can see themselves as heroes too.
So I know that seeing the Marvel movies with your dad was a big thing for you. What do you remember about your experiences, seeing the Ant-Man movies specifically with your dad?
KN: I think I was blown away by how the theatre was so full. I think when you’re little, for me, it was like a cool thing to go to the movies. It was kind of a big deal. I really, really, really want young people to see this movie and get excited about the next generation because I grew up with these movies.
I love Iron Man, I love Ant-Man, and it’s because I’ve lived with these characters so long. I don’t know what people are gonna think. But it would be really cool if a 10 year-old, 12 year-old, eight year old little kid saw this movie, and I got to be a part of their life. If I get to do another movie, I don’t know, but these movies…they are a part of my life.
I’m a fan. I go with my friends to these movies. So Spider-Man, you know…all of them. One of my friends from high school posted “I remember going to see Spider-Man with you and you saying you want to be a superhero.” Like I’ve always dreamt of this. So it’s not just Iron Man or Ant-Man. It’s all these Marvel movies. Yeah, they’re very…magical. I think they are magical. Like we don’t all live in fairy tales.
But there’s a bit of magic.
KN: There’s a lot of magic.
Watch our full interview below: