Lizzy Caplan in 'Save the Date'

Opening opposite The Hobbit tomorrow pretty much dooms Save the Date to be a period at the end of the tiny footnote at the bottom of this weekend’s box-office story. But the movie, which premiered at Sundance and stars Alison Brie and Lizzy Caplan as sisters — one blissfully engaged to be married, the other making every effort to avoid the institution — is a refreshingly complex look at modern movie romance. Brie’s responsible older sis is aggressively planning her wedding to Martin Starr’s bearded drummer, while Caplan’s Sarah is having second thoughts about moving in with the band’s lead singer, played by 500 Days of Summer‘s Geoffrey Arend. (Watch an exclusive clip from the film after the jump, as Sarah meets her “rebound” guy, played by Mark Webber.)

Caplan, who’s earned a loyal, if cult-y, following after memorable performances in Mean Girls and Party Down, as well as her recent turn as a coked-up bridesmaid in Bachelorette, spoke to Entertainment Weekly about what she loved about her character, and when we can expect that Party Down movie.

ENTERTAINMENT WEEKLY: When I saw Save the Date at Sundance earlier this year, it made me think of Reality Bites and Before Sunrise. Were there similar films in the back of your mind as you read this script?

LIZZY CAPLAN: If we’re anything like Reality Bites to anybody, then I’m a fan of that because that movie definitely was one that I was raised on. I was really excited to read a script that reminded me of that type of movie — like Singles, too — because they’re not really making so many of these kind of quiet, character-driven, relationship dramas. I miss seeing movies like that.

I hesitate to use the term, but so many of what we know as romantic-comedies revel in the idea of true love and the quest for our soul mates. Part of what I liked about your movie is its more sober approach to romance.

Obviously, there are endless movies made about the complications of relationships, but what really drew me to this movie was this examination of a breakup that occurs when nobody’s done anything really horrible to the other person. What I find in reality is that relationships that end because of circumstance or timing — where you still care about or love the person, but you just can’t be together anymore — are by far the most difficult breakups to go through.

I would say the film is unusual in the sense that, although your character, Sarah, is the spine of the story, the audience gets a real sense and appreciation for all five characters’ point of view.

Yes, I totally agree. [Normally] there’s always somebody who has to be kind of the bad guy, and I was really in to the idea that we didn’t have one of those. In fact, I break up with one guy who seems to be one of the nicest guys in the world, only to start shacking up with a guy who’s potentially even nicer. And I thought that was really interesting. How do we raise the stakes, how do we make a movie watchable without there being a true villain in it?

Sarah actually breaks both guys’ hearts in the movie, in various excruciating ways. Are those days you dread as an actress, or are those scenes fun in a way.

[Laughs] Any emotional stuff that I have to shoot, those are the days that I’m more nervous about. I don’t relish breaking their hearts, but at the end of the take, you can just go and laugh and go to craft services and be buddies again. So I rarely take that part of the job past the word, “Cut.”

I read somewhere that you identified with Sarah more than any other character you’ve ever played. In what sense?

I connected to the idea that everybody around you is pushing you in a direction that feels wrong to you, even if on paper it seems completely fine. That just really struck a huge chord in me because I’ve made some decisions in my life that have gone against what everybody who’s close to me has told me to do or has done themselves. I didn’t go to college, and everybody I’ve ever met in my life and everybody in my family for multiple generations all went away to college. And I didn’t do that. I tried to be an actor instead. That’s not a romantic example, but stuff like that where you just want to live your life slightly differently and dealing with the reactions of other people, which used to be something that was very difficult for me. I guess that would be the main thing.

Alison Brie plays your older sister in the movie, and you both seemed really comfortable with that relationship.

Alison and I both have sisters and I think that made our job so much easier because there’s a way that you behave with your sister that you would not behave with anybody else in your life ever. You can be a little crueler or harsher to your sister than you can to any other woman in your life, and I think there’s some loveliness to the safety of that unconditional love. The drawback to that is that fighting with your sister is so particularly frustrating. You can argue with your sister and not apologize right afterwards, even though you probably should.

You’ve known Martin Starr since you were a kid, and you both were on Party Down. Are there still plans to make a Party Down movie?

Yeah, definitely. I just ran into John Enbom, who’s one of the creators of the show, and I was grilling him about it because I have been asked this question so often.

Sorry.

No, not at all. I mean, listen, I want this movie to happen so badly. We all do. It’s just scheduling and making all the pieces fit together that is going to be a bit of challenge. But the good news is, with every passing month, more people discover Party Down, so we may actually have a substantial audience by the time we get to make the movie.

Is there a script? Or just a concept?

I don’t think I’m allowed to say that. [Laughs]

That answer actually gives me real hope. You also appeared in that Marvel superhero short, Item 47. Are you hopeful that you might get to explore the Marvel universe some more?

I suppose that’s always an option. I know they’re making that S.H.I.E.L.D. TV show. I think that would be the natural trajectory for where my character ends up. But I’m doing another television show so I can’t be on that one. But I like all those guys at Marvel quite a bit, and I’d love to work with them again. But as of now, I can’t do their show and I think that’s the next thing they seem to be focusing on.

The other show is Master of Sex for Showtime, yes? Based on Masters and Johnson, the married couple who did groundbreaking sex research in the late 1950s.

It’s just gearing up to start production. I can’t wait. We’ve all read the book that our show is based upon, and they’re story is so fascinating. Michael Sheen plays Masters, and I’m actually on the fence on what is more fascinating to me at this point: the strides they made in sex research — especially for women, especially for the feminist movement — or their own personal relationship, which was totally twisted and sordid and very very odd. I think it’s going to be pree-tay explosive.

So Save the Date opens tomorrow in just a couple theaters, opposite some movie about hobbits. Fair fight?

I’m pretty sure we’re going to beat them in the box office. Watch your back, Hobbit.

P.S.: Even if Save the Date isn’t playing in a theater near you, it can be downloaded right now on iTunes and VOD.

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