In its sixth and final season, HBO’s Girls is telling a story within a story about itself. Adam is making a film about his tumultuous relationship with Hannah, how they met, and how they broke up. He needed an actress to play the Hannah role, which leads to an uncanny bit of meta casting: Girls had to find someone to convincingly play Hannah who wasn’t Lena Dunham. They cast Daisy Eagan, who, yes, looks a lot like Dunham.

Eagan has her own strange and slightly surreal story to tell too as someone who recently made her way back to acting and performing. At 11 years old, she was the youngest ever female to win a Tony for her performance as Mary Lennox in The Secret Garden — an emotional experience that coincided with her mother’s fatal cancer diagnosis. Eagan, now 37, has returned to the production that originally gave her fame, this time as Martha, the chambermaid who sings “Hold On” to the young Mary. Vulture spoke on the phone with Eagan about getting mistaken for Lena Dunham, her cathartic return to Secret Garden, and the extended version of Adam and Hannah’s origin story.

The casting as Hannah’s stand-in is really uncanny. How did you get this role?

Well, it’s funny. When Girls first premiered five years ago, I had just gotten back into acting at that point; I had taken a break. My agent called and said, “You know, you should play Lena Dunham’s sister on Girls.” This was before we knew she was an only child. For five years, people have been telling me that I look like her, especially when we both have short hair. When this part came up, it was just to us, it was so obvious. And I hadn’t seen Jen Euston [casting director for Girls] in a long time because I’d been out of the business. When I came in, she even said, “Do people tell you that you look like her?” and I said, “Yup, all the time.” I even make jokes about it. When people ask, “Where do I know you from?” or “You look familiar,” I say, “I’m not Lena Dunham.”

Have you ever pretended that you were?

Sort of. I did a goofy live Halloween show for a friend the year before last year, and I didn’t dress up so the joke was that I was just dressed up as Lena Dunham for Halloween. It was kind of perfect.

What was the audition like?

I hadn’t watched a ton of the show before having this audition so I brushed up on it, especially the earlier seasons because I knew that that was they were looking for. They had me come in and read with Lena and Jemima [Kirke] and Adam [Driver] at HBO, which was lots of fun. Then they had me come back because they wanted me and whoever I was up against, they wanted to see us do an impression of Lena, which is not what I had been doing. So they gave me the scene from the first season where she goes with the eyebrows and tells them that she doesn’t want to get pictures of his penis that was meant for somebody else. So I did that scene and then I just did a little ad-libbed monologue that I came up with straight to Lena, just basically saying, “I think that you should cast me and I should be your muse and I don’t understand why I have to keep coming back and, you know, doing this and blah blah blah.” I was doing it as Daisy as Hannah. It was a good time.

What mannerisms were the focus of your Hannah impression?

Well, it’s interesting. She has a very unique cadence. One of the first things I noticed about her is that upspeak, where everyone talks in a question all the time. She doesn’t exactly do upspeak so much as it almost sounds like maybe she did a lot of upspeak when she was younger and had trained herself out of it. So she has the kind of stilted way of talking where you might normally expect somebody like that to be doing an upspeak, but she is not actually going up at the end of a pause. And she uses her head a lot for emphasis, and looks off a lot, which actually I do too. I have to put myself on tape frequently for auditions and that’s something that I had noticed a while ago about myself. I don’t know why. But she does that as well.

What was it like filming the spanking scene? Was Adam actually hitting you?

Yeah, we tried it several different ways. First, we tried it with butt pad, but the butt pad was too obvious. We tried it with him not hitting me at all, but that didn’t look right. So he just, as gently as he could, while still selling it, did it. You can see when I jump on him toward the end of that scene, that there’s a big red mark on my butt, which is genuine. But then, you know, I also sold it by like moving the table as much as possible to make it look a lot harder than it was.

On Girls, we haven’t seen how Hannah and Adam actually met, so the fact that you got to play their origin story is fun.

Yeah, it was really fun, and that scene actually didn’t come about until after I’d booked it. They decided to add it on. The original was much longer — the original scene was like a good five or six pages. It was way too long.

What happens in the scene?

Oh gosh, let’s see if I can remember. There was a whole discussion about her diet, and he’s offering her unsolicited advice about what she should be eating for optimal health. She says that something is only a carob almond so it’s not real sugar and that’s when he freaks out about refined sugar versus unrefined sugar. It was very interesting reading that scene because we had never seen their origin story. Honestly, I don’t know if that’s truly their origin story or just what Adam wants their origin story to be.

You know, he’s six-foot a million and I’m barely five-one, so he is intimidating, in a way, especially in that scene. He’s offering all this unsolicited advice and he’s so powerful right out of the gate. Saying, you know, I’m going to call the police. And initially, he’s holding a giant knife because he’s cutting fruit. Also, if you’re going to peel all of the layers back, it’s interesting that that’s Adam’s version of the way they met, considering that he does come off as not the sweetest guy in the world. What I found interesting about that as a woman, and as a small woman, is this idea of being attracted to somebody who is kind of scary. At first glance, anybody on the outside would look at that and go, “Nope, that’s not healthy, don’t do that.” But there’s something so magnetic about it and so irresistible that we jump in head first with somebody who is basically saying, “Good, if I hurt you it means you’ll remember me,” which is so unhealthy. The opportunity to play that dynamic was really exciting. It feels very raw.

You’ve been on tour doing Secret Garden. Is it strange to go back to that production? It was such a big part of your life early on.

It’s definitely strange and I feel very fortunate to get to do it. In a lot of ways, it’s very restorative for me, because my mom was very ill when I was doing the show originally and now I get to go back and address my inner child and put that stuff to bed, which is nice. And I’ve had some mixed feelings about it. I was asked recently if I would do a concert version not attached to the production, and I thought, you know, I don’t need to be the woman who goes around doing Secret Garden all over the place, willy-nilly. I’m a part of this production because Lucy [Simon] and Marsha [Norman] asked me to be a part of it and that’s important to me. It’s a great opportunity to revisit and accept some stuff from the past.

Do you think that having success at such a young age was a double-edged sword?

Oh, yeah. Absolutely. I wouldn’t wish child success on anybody. My son who is going to be four in May, he’s very gregarious and very outgoing and he plays the drums and he loves to sing and dance and entertain and I’m terrified because I know that’s a harbinger for things to come. I just wish that he could be an engineer and go to MIT and design a special telescope. So yeah, there’s a lot of psychological stuff that goes along with becoming successful at that age, especially because it was a specific psychological development phase for me, being 10, 11 years old. I think I missed out on being a kid and that screwed things up for me for a while, and it took me a long time to reconcile all that and be okay with what my childhood was or wasn’t and create my life with all that integrated into it, instead of despite it. Embracing it.

How did you return to acting and performing?

I had been out for almost four years. I was working a regular job at a university. And friends were asking me if I would come sing a number in their cabaret, and initially I kept saying, “No, no. I don’t perform anymore, I don’t do that anymore.” And then for whatever reason, I thought, “Why not?” I’ll go do this benefit for the actor’s fund. And suddenly, performing felt really different. I was less terrified than I had been before I had gotten out. I had developed some pretty bad stage fright, and I would freeze up onstage and get really uncomfortable and I had overcome that somehow. Maybe the stakes didn’t feel as high, so I was more comfortable just being myself. I rediscovered a love of performing, especially with making people laugh in one moment and cry in the next. It makes you feel powerful, to be honest. And I remembered that part of it; I remembered the performing part of it as opposed to the business part of it. And so, I had a loss of good judgment and I went back into it full-time, and it was definitely the right choice. I started working again very quickly, thank God. I feel very lucky. But yeah, I had to get to a different place with myself and feel more comfortable with myself and know myself better in order to get back up in front of people and be like, “This is who I am and some of you are going to love it and some of you aren’t, and that’s fine.” Whereas before, it was the constant terror of not pleasing every single person all the time.

Last question: Did you get that job packaging human breast milk?

[Laughs.] The interview actually ended up never happening, which is really too bad because it would be great to be able to put a bow on that story and say, “By the way I didn’t even get the job.” But it ended up never even happening, which in some ways is even more ironic. That that tweet did what it did for me, and then the thing never even happened. Such is life, I guess, right?