Sunday night’s series finale of HBO’s Girls went in an unexpected direction, concluding the show on a quiet, contemplative note as it explored Hannah’s life with her newborn son (named Grover) in upstate New York. The only other regular characters appearing in the episode were Hannah’s best friend, Marnie (Allison Williams), and her mother, Loreen (Becky Ann Baker).

Marnie arrives on the scene to help Hannah (Lena Dunham) take care of Grover, explaining she wants to help Hannah adjust to this dramatic shift in her life. “I still have a lot to give—a lot. So why not give it to you and this little angel?” Marnie reasons, noting that she has “won” the Hannah friendship competition. “I win; I’m your best friend. I’m the best at being your friend. I love you the most,” Marnie says, after waking up next to her college bestie at the episode’s beginning.

Marnie gets up to all sorts of hijinks in her new role as caretaker and support system, belting Tracy Chapman’s “Fast Car” while driving with Hannah and Grover (to Hannah’s dismay) and also pursuing a long-distance, uh, romance via Facetime. At episode’s end, though, Marnie—after a revelatory conversation with Loreen—is ready to move out of the house, and even mentions that law school might be a possibility for her down the road.

We spoke to Williams—currently starring in the surprise box-office smash Get Out—on the Saturday before the finale, and then on Monday morning afterward, to discuss the conclusion of the series.

VF.com: The finale felt like a really nice resting place for Marnie in the show’s universe.

Allison Williams: Yeah, I feel good about where Marnie is heading. . . . I worried that it didn’t answer enough questions explicitly, that people would be dissatisfied by not having a postscript that says exactly what happens to everybody. But I think that to do that would feel very much outside the world of our show. I bet everyone that has been watching the show from the beginning kind of expected a finale like that. But I feel like it left on a kind of hopeful note, and I think leaving the world of the show, leaving Brooklyn, helped to kind of ease our transition out of Girls. The way I described it to my friends was that it was like an epilogue.

What was it like actually watching the finale for the first time Sunday night?

It was intense. I was with Lena, who of course had already seen it many, many times while editing it. It was really nice to be able to be with her to watch it. I loved that it felt very much . . . somehow totally right. There was an inevitability to the way that it concluded that can only exist in hindsight. I just felt proud of Marnie for at least trying, even though I knew she was only doing it to give herself purpose. I don’t really fault her for that, because what else are we all looking for? But I also like that she’s finally making a decision about where to go in her life that is based on who she is instead of who she wants to be. All the rules about law really appeal to her because she loves rules. That’s a logic line that we haven’t really heard from her before, of working backwards from something fundamental about her personality and then thinking, “Well, given that, what should I do next?” I feel very comfortable and sated waking away from Marnie in that place because it feels like she’s going to be O.K.

Video: What To Know Before Going Blonde, According to Allison Williams

I’m curious how you felt about the idea of her going to law school. It felt to me like it could so be her.