When we first meet Kate Galvin, the frosty English heiress at the center of You Season Four, she is reclined on the couch, pleasuring herself. Her neighbor Joe (Penn Badgley), once again assuming the role of Peeping Tom, is so entranced by the performance he burns his tea. In lieu of seeing things to completion, he throws on a coat and scarf, and goes for a stroll. What in the hell has happened to our sexy, sardonic serial killer? This isn’t the same uncontrollably horny weirdo who beat off on a city sidewalk, or in a grocery store parking lot. Has the Ted Kaczynski of love bombing gone soft on us? Or has he finally met his match?

It turns out he has. You see, Kate is not like Guinevere Beck or Love Quinn. She is steely, sophisticated, and resistant to Joe’s charms. The first time they have sex — in a secluded garden of her choosing — she refuses to let him kiss her. When they happen upon a dead socialite in a country home, she demands they dispose of the body. Kate, it turns out, is the daughter of Tom Lockwood (Greg Kinnear), a multi-billionaire corporate raider whose body count likely puts Joe’s to shame. Then again, so does Kate’s. She brokered a deal that left a bunch of kids with cancer. Not even Joe’s stooped to harming innocent children.

That Kate is played by Charlotte Ritchie will come as a surprise to U.K. audiences, who know her as one of their brightest comedy stars, with standout roles in Succession creator Jesse Armstrong’s Fresh Meat and the laugh-a-minute sitcom Ghosts. Thankfully, she passes the test with flying colors.

Stop reading now if you wish to avoid spoilers.

The final episodes of You’s fourth season see Joe come to the realization that Rhys Montrose is a figment of his deeply twisted imagination, and he is the actual “Eat the Rich” killer. After suffocating Tom to death, and allowing Marienne to escape his plexiglass vault, Joe attempts to take his own life by jumping off a bridge — only to survive. Kate visits him in the hospital and the two confess their undying love for one another, at which point the action cuts to a Manhattan high-rise, where Kate and Joe, now a New York City power couple, are being profiled for The Cut. Joe steps away, looks at his reflection in the window, and sees Rhys staring back at him.

Charlotte Ritchie spoke with Rolling Stone about the fourth season of You and so much more.

There are elements of a classic romcom at first in this season of You where Kate despises Joe and then warms to him.

It was so satisfying in the beginning to get to be so cold to him. With everything I know about the character, there was something about it where I was like, yeah!

Were you two so in-character that you didn’t socialize when you first started filming?

It definitely was organic in the sense that we hadn’t had the opportunity to become friends before that, so those scenes where we were disconnected — it wasn’t like we had rehearsals and got to know each other very well and then had to draw back. In some way there was a distance. But it was really lovely, on a personal level, to connect more with him and play those scenes.

How did you two end up becoming friends? Was there an icebreaker?

There was a moment where I made a really dumb joke and I think he heard it and was like, “Huh… that’s not the kind of joke Kate would make!” We laughed about it and it was nice for us to think that we weren’t these serious people who had these murderous [instincts] — not that that’s true. It’s nice when you have a moment where you really see each other outside of the job. From that point, we had a really similar sense of humor and he really made me laugh. He does this bizarre English voice where he’s sort of this small Victorian boy. I hate it. It would come out all the time and made me laugh quite a lot.

I read an interview with Penn where he said that he got Covid during filming and was bedridden for ten days, and he spent that time listening to Kendrick Lamar and watching all of your show Ghosts. Did he emerge with all of these questions about it?

That was so sweet! Yeah, he did! I think he emerged and was like, hey, she does some other stuff, that’s pretty cool. And I was like, yeah, if you just looked me up, you’d know! [Laughs] I’m only kidding. Am I kidding? I was so deeply chuffed. I’m so proud of that show and was really pleased to share that with him. My character in You is so mean and it was nice to share a different side of myself with him. And I was really pleased that he liked it.

Kate and Joe’s first intimate encounter occurs in a garden. What was it like to film that scene? It’s quite a funny sex scene because there’s someone snooping on you two as well.

Yes. It’s very beautiful! It’s a lovely little area. I don’t think it exists in real life and they constructed it for the show, in case anyone’s getting any ideas about visiting it. These poor residents are like, “Please! Stop visiting the garden!” That sequence was a rewrite of another sequence, and the purpose of that was to begin to soften their relationship — the way Kate falls over and doesn’t make it as sexy as she likes it to. The show’s not from her perspective but if it were to be, it would be very much that she’s using him to have some sort of release from the situation she’s in. The significant thing to note is they don’t kiss until Episode Six. They have sex three or four times before then, so there’s no intimacy in their connection. She’s not interested in an intimate connection, so it’s all very functional.

I heard that you were first turned off by Joe when you started watching You, and I’m curious why you think the women within the reality of the show are turned on by him?

That was just because I was in a particular mood looking for something that wasn’t a guy being a creep, but having gone back and watched the show, that was just my frame of mind, really, because I think it’s great. Oh gosh! The reason they love him is because he’s unbelievably caring and present — present is an understatement — but their perspective of him is the one that he presents, which is that he’s caring, and loving, and thoughtful, and funny, and he’s obviously great in bed, as far as what’s implied in the show. And he’s handsome. They’re satisfied in all areas.

Penn’s been vocal in interviews about how he wanted less sex scenes this season out of fidelity to his relationship. And you notice on the show how all the sex scenes cut away quickly. What was it like for you to film those that way, where they’re kind of abbreviated?

Yeah. I’m trying to think… there were only a few. I think you get what you need, basically. And it’s all very carefully choreographed now. But it’s always a strange thing to do!

In the finale episode, there’s that moment in the hospital between Kate and Joe where they finally see each other. They’ve both killed many people. Joe has done it in a more intimate fashion whereas Kate the billionaire killed on a larger scale.

There’s a directness to his experience with that and for her it’s very indirect. I have to believe that she’s witnessed that level of violence at some point. There’s a feeling that she’s been aware of henchmen. I have this vision of her not being totally immune to seeing that kind of violence before.

When they dispose of the body together in the mansion it looks like she’d done that before.

Exactly! That’s what I’m referring to.

And the end sees Joe back in New York. Kate and Joe have received a gushy profile in The Cut, which contrasts with that other piece in The Cut about Joe and Love. What do you think that ending says about power and the media? Because that final scene is really them gaming a journalist in painting themselves as this innocent, loving power couple.

You’d have to believe it’s true, right? History’s proven it to be true. You can see the power of lobbyists and how money exchanges hands. One good thing about this age, even though things are quite overwhelming and confusing, is there’s this peeling-back of the level of power that some individuals have. The crazy wealth and power that some individuals have is mind-boggling. I still don’t quite know what the show is saying there, but of course it’s possible for them to create a puff piece. I guess the lesson is: Don’t believe everything you read.

Joe’s not only back in his old stomping grounds at the end of the season, but he’s never had these kinds of resources before.

He’s never had these resources or had someone who’s really in cahoots with him in a way that he feels in control or on a level with. It’s scary that he’s got a friend and partner. And he’s never been so integrated in his feelings about his violence, and himself. That’s spooky. All through the other series he’s been in denial that he’s a bad person and felt, oh, this is just this thing I do. There’s something about that final note where he’s with someone who’s like, I can see that you’re both and it’s fine by me, and he’s like, “I’m just here to help.” Oh no! He looks in the mirror and Rhys is there, so that signifies that he’s in a new place mentally and it’s scary. But also thrilling.

Now you’re gonna be killing high society New Yorkers together.

Maybe! Or maybe the whole series is about them genuinely setting up charitable organizations. And I’m sure people would love that! Because that’s what they love about the show. [Laughs]

I have to ask about Season Five. I’m sure they’re going to green-light one because the show continues to hit No. 1 on Netflix, and showrunner Sera Gamble’s said she has the upcoming season already mapped out. You must be returning then, right?

Well, there are whispers but — and I’ll tell you this hand-on-heart — I don’t know if it will be, when it will be, if I’m in it, and to what extent. There’s a good chance I’ll have to be in it because I’m in the last scene of the series before. Or it could be that he turns up six months later and someone goes, “Who’s Kate?” and he goes, “Who?” She’s gone! Fifteen years later, he’s living on an island somewhere and they don’t have to explain where I’ve gone because I’m obviously dead. I don’t know. I’m interested to find out if that’s for sure. I’m waiting with bated breath on my emails and my phone. And that’s the joy of being an actor — to find out whether it’s happening or not!

Does looking back on your period in the girl group All Angels feel like a weird fever dream? You were pretty young and even performed in front of the Queen of England a couple times.

What I find so amazing is how late my autonomy came in. It was brilliant, but I was fully on, “You go here, do that, wear this, do this.” I didn’t ever think creatively about it. It was a great job, and I was earning money at 17, so I was like, yeah, I’ll do whatever. I like singing and I’ll go on tour with people I get along with. It really was a fever dream, though. Some of the outfits! But the girls are still really good friends of mine.

I saw that one of your first roles was as a background actor in Harry Potter and the Goblet of Fire.

I mean, I wouldn’t big that up too much. My eyebrows maybe feature in one three-minute scene. It was a scene with Harry, Ron and Brendan Gleeson, and I learned a huge lesson on that. I felt the other actors weren’t acting enough in the shot and thought, “That’s never going to translate to the cinema screen. You’ve got to do more!” And my eyebrows are as if someone’s tied two laces and they’re absolutely ricocheting like some sort of magic wands. I got all my friends together and we went to the local cinema at the Stretton Odeon and I was like, “This is going to be amazing!” And I was like, “Oh my god, what am I doing!” I realized you have to be smaller for the camera and not bigger.

I watched this Glamour video interview where they asked the You cast questions, and you were all asked who was the least likely to leave the dancefloor. Penn said it was you, and that you’d demonstrated this on several occasions throughout filming. Where were these You dance parties?

We did have a little party with some of the crew and some of the cast. There was a dance party there. I’ll tell you who else doesn’t leave the dancefloor: Tati. She’s amazing. I had a small [party] with a friend and everyone came from the cast, which was lovely. There was a lot of dancing. Penn stayed till the lights went up! But listen, I love to dance. There were a couple of occasions. He said he hadn’t been to a party in a long time — none of us had been to a party in a long time — but there were some bars in the Kings Cross area…