For Madelyn Cline, “Outer Banks” wasn’t just her big break; it’s made her the actor she is today. She got her start in commercials and modeling before appearing on HBO’s “Vice Principals” and Netflix’s “Stranger Things.” Then came her turn as the rebellious Sarah Cameron on Netflix’s “Outer Banks,” an adventure drama about a group of teen treasure hunters. (The second half of Season 4 drops on Nov. 7.) Since the series’ 2020 premiere, Cline has stolen scenes in the star-studded “Glass Onion”; next year, she’s headlining “I Never Forget What You Did Last Summer.”

1. How has playing Sarah on “Outer Banks” shaped you as an actor?

She and I have grown up together. I’ve spent the majority of my 20s with Sarah, so she’s very special to me, and I feel very protective over her. In a way, we’re holding each other’s hands through all these different experiences. The things that I am experiencing get to inform her and vice versa.

2. As a child, you worked in modeling and appeared in commercials. What was it like transitioning to acting as an adult?

“Outer Banks” has been such a boot camp, in a more technical sense. Forgive me, but it’s truly an environment where you piss or get off the pot. A lot of times, it doesn’t feel like we’re acting because we’re on location, running around in the elements, chasing the light, and running out of time. So in the moment, it does feel very high-stakes. We move really quickly, so you have to come prepared. If you don’t, be prepared to see work that you’re not proud of on the screen. It truly is the best training ground for actors.

3. Who have you learned the most from over the course of your career?

I think the best thing to do is just watch and observe other actors in their space, doing their thing. Working on “Glass Onion,” I felt so weird, because I would just stare. Watching actors who have been in it for so long be so free was so inspiring. I would just look at them and be like, That’s what it’s about! It was truly a master class.

4. Have you settled into a specific approach to your craft?

That’s a scary question because it’s so incredibly personal—and, of course, I am still learning so much. Preparation-wise, something I learned very early on in acting classes was the importance of [paying attention] to my reaction the first time I read the material, and making sure to take note of that. I’d walk away, come back to it, and then repeat the process. I slowly realized that by letting myself digest it [that way], that information and my emotional response starts to sink in and steep.

I also try to not get married to anything and, on the day, allow my physical environment to inform a lot of the choices I make. It’s a funny balance; like, you want to prepare, but you don’t want to overprepare.

5. When did you get your SAG-AFTRA card?

When I was around 10 or 11, I’d done enough commercials that I had to get a membership. I didn’t know why everybody was really excited about it, but I was like, OK, cool. I have a card now. Mom, can we go get a wallet? [Laughs]