Every night at 7 p.m., Sebastian Stan peers outside the window of his Manhattan apartment and cheers. It’s become a nightly ritual for most New Yorkers to honor doctors, nurses and other essential workers who are on the frontlines of the coronavirus crisis.

“It was crazy the other day,” Stan tells Variety. “There was a woman on the street; it broke my heart almost. She started playing ‘New York, New York’ by Frank Sinatra, just blasting it out loud. And everybody was just like, ‘We ain’t going down, baby. No matter what.’”

Stan knows, better than most, what it means to be a New Yorker. Early in his career, the now 37-year-old actor had a reoccurring part on “Gossip Girl,” which shot throughout Manhattan and Brooklyn and has cameos from notable restaurants and clubs. But Stan’s career really took off after he played Steve Rogers’ best friend Bucky Barnes in “Captain America.” The notoriety from the Marvel Cinematic Universal has afforded him chances to take risks on independent films ranging from “Destroyer” to “I, Tonya.”

Stan’s latest movie, “Endings, Beginning,” is now available to watch in homes after premiering at last fall’s Toronto Film Festival. In the drama, directed by Drake Doremus, Stan plays Frank, who meets a woman at a party (Shailene Woodley) that both he and his best friend (Jamie Dornan) start to romantically pursue.

Over an Instagram live conversation with Variety, Stan spoke about making “Endings, Beginnings” through improvisation, when he might return to the Marvel Universe and why he never wore a belt on “Gossip Girl.”

Can you talk about working with Drake Doremus. There’s no script when you sign on for one of his films, right?

Right. There’s only an outline, which is about 70 pages and it’s sort of like a general, loose direction of where he wants the story to go. Everything is discovered in the moment on the day. A lot of what you’re going to see in the movie is improvised. One of the things he’s such a master at is being able to take all these moments and piece it together into a performance. I have no idea how he edited it all together.

You and Jamie Dornan play—

Star-crossed friends!

… who are both vying for Shailene Woodley.

Yes, we are good friends in the movie and our friendship is tested when we meet Shailene. It’s a very honest movie about how confusing relationships are sometimes and really how messy they are in terms of a beginning, middle and end. Things don’t just always close. One thing I’ve love about Drake’s movies, especially “Like Crazy” and “Newness,” is the vulnerability and intimacy that he seems to capture, the authenticity of the connections between people.

Jamie told me he wanted to play the nicer guy, and that you picked the bad guy, because that’s more fun.

I would have played either role. Drake put me in that role. I was just happy to be part of the movie, it didn’t matter what he was going to choose. I think the way it was cast was the right way.

How do you prepare for a scene knowing you’re going to improvise most of your dialogue?

It’s definitely scary because you’re like, “How interesting of a person am I?” When you [normally] have a scene, you have lines, you have protection. But we had a direction. A lot of it comes from the dynamic you build in rehearsal. And being open with each other. Shailene, acting opposite her, it was total vulnerability, total honesty. It’s a lot easier when someone opposite you is giving their all.

Were their moments that you improvised that made you cringe?

Every scene made me very upset. Every scene made me question why I’m doing this. And why my relationships haven’t really worked. No! It’s a very exposing process. There are takes that we probably shot for 20 minutes straight without cutting and we would go all over the place. You go home and wonder if any of it is good. But it’s kind of nice because it gets you out of your head; it gets you out of your comfort zone. You just show up tomorrow and all you’re trying to do is be as present as possible and available to any accidents that might happen.

How do you feel about people watching “Endings, Beginnings” in their homes?

If we could, I wish we would have had different circumstances for the movie. I think it’s so beautifully shot — every frame, every single angle. I’m also grateful it can be watched now. This is a crazy time. It’s a testing time. If people are at home and they want to tune into something else for two hours that makes them think about something else, then why not?

How have you been passing the time in self-isolation?

Talking to myself. By the way I’m in New York. We’re 10 minutes away from 7 p.m., baby. That’s the moment of the day — for people who don’t know — at 7 p.m., people go out to their windows and they start clapping for all the workers and everybody when their shift changes. It hits home, because everybody is on the same page. No matter where you are, no matter what apartment you‘re in, we’re all connected for that moment. There’s something very special about that. It’s about those people who hardly ever get any kind of notice for their work.

I don’t know how it is for you. For me, I try to do something productive every day. I’ve got some writing that I’m doing and some reading. I haven’t been home in a long time. It’s been nice to be home and finally hunker down. And then I just think about all the things I’ve taken for granted, and how nice it is that we’re so lucky to be able to do the things that we do in our life. I just hope when we come out of this, we don’t blow through that. That we maybe learn to take each other in a little bit better. The fact that we can be so close and you could touch somebody, you can hug your mother whenever you want and go over there and be close to them.

In New York, it’s hard because we all live in a concentrated space. Even going for a walk, there are too many people outside who aren’t wearing a mask or respecting social distancing.

I think we have that problem everywhere, not just in New York. What sucks about it is all it’s going to do is make everything longer. Yeah, it’s a nice day out — and you’ve got to take care of your mental health, too. If you want to go for a walk, there’s times you can go for a walk, like really early where it’s empty. But this isn’t the time to be going and having a picnic in the f—ing park, which is still happening.

I wanted to ask you about your career trajectory, because you’ve taken some risks in the last few years. You starred in the “Avengers” franchise, but you’ve also done some great work in independent movies, including “Destroyer” and “I, Tonya.” How do you choose what you want to do?

I think it’s all about a character or the directors. I’m just trying to surround myself with people I admire who I like to think are a lot better than me. And by that, by default, I’m going to end up learning. A lot of those choices are based on finding directors who have a very specific vision and honoring that vision. I don’t think movies, even TV, is not really an actors’ medium. It belongs to the writers and the directors. I’m just trying to do things that are interesting to me and kind of make me scared and keep me on my toes, because I’m a very bad self-critic. If I feel like I’m leaning too much into my Sebastian-isms, I get critical about that. I try to mix it up.

How did starring in “The Avengers” franchise change your career?

Well, it was huge. It was 10 years ago, in 2010, when I came in. Looking back, I feel like I had half the amount of experience and knowledge that I do now. In a way, I felt like I grew up with the franchise as a person myself and I feel like that character grew up with me as well. But I don’t think any of these movies that you referenced would have been possible without it. I wouldn’t be here without it.

How did feel to have “Avengers: Endgame” become the most successful movie of all time?

That’s just wild. You don’t even think about that. It’s crazy to think it’s bigger than “Titanic.” I went to see “Titanic” way too many times in the theater. It’s exciting, because 10 years worth of filmmaking went into making [“Avengers: Endgame”]. The fact that people went out to see it and support it so much only shows how much they love the characters, how much they’ve invested in the past 10 years. And they feel like in a way they grew up with the movie.

Is there anything you can tell us with your involvement of the future “Avengers” movies?

You know, I know nothing about that. I’m just a man. [Laughs.] We got to figure out a couple other missions first before we even get there. I’ve got to deal with this other person. It’s been nice to have a break from him, Anthony Mackie. It’s nice to have a little quiet in this quarantine without him. But we got to figure out some adventures together first before we get there

Our social media editor Meg Zukin wanted me to ask you if you had any insight into what’s happening to your character Carter Baizen on the “Gossip Girl” reboot.

The old Carter Baizen, he’s still out there on the island of Maui or something — who knows. I can’t believe we’re having a reboot. It’s kind of cool. It’s kind of crazy. It kind of reminds me of how old I am. That wasn’t even that long ago.

It doesn’t feel that long ago.

It was 2008. It was like a different world. But it was a great job, like I was so happy being a part of it. I was in New York. I was working with my friends. And also, that show was at that moment. Everybody was talking about it. I remember going into the fittings and being told, “You’re never wearing a belt again from a fashion standpoint.” I was like, “OK.” So I never wore a belt again.

Why weren’t allowed to wear a belt?

In terms of “Gossip Girl” fashion, I think that set a couple of trends. I don’t know if I remember them entirely. But with men, I remember that. Don’t wear belts. Just watch. There’s not a belt on that show.