Lizzy Caplan and Alison Brie plays sisters who are both facing questions about their relationships as they near the time when everyone expects them to settle down and start their own families. Brie's Beth is engaged and planning her wedding to Martin Starr's Andrew, a drummer in a band who can't be bothered to have an opinion about place settings or organic catering. Caplan's Sarah is about to reluctantly move in with her boyfriend Kevin (Geoffrey Arend), Andrew's band-mate.
The opening scenes, featuring Caplan packing up all her belongings, including the still-dirty dishes in her sink, are indicative of quirky comedy, a type of film Save the Date never actually becomes, unless you find heartbreak and emotional honesty just gut-bustingly hilarious.
The turn toward the dramatic occurs when Kevin, despite prudent advice from Andrew and Beth, proposes to Sarah after a gig. Arend's performance as Caplan walks away in silent anger is agonizingly good. His crushing despair is shockingly credible.
From there the film navigates the fallout of the breakup through its impact on Beth's and Andrew's engagement and Sarah's new relationship with Mark Webber's Jonathan, a marine biologist (yes, really) who patronizes her bookstore just to get a look at her. Because you see, when you do it in a movie, it's not creepy.
This is a film that is really little more than a showpiece for some talented actors who otherwise don't get anything but supporting roles in studio comedies. It's nice to see them get a chance to show off their full range, even if they had to settle for a less-than-great script to get that chance. Caplan's character in particular is underdeveloped on the page, as her fear of commitment and need to preserve her independence are never explored or explained. The lack of proximate cause makes her seem not worth all the trouble she puts Kevin and Jonathan through, but they keep insisting on how special she is. Other than looking like Lizzy Caplan, what does she bring to the table?
The film is also soured a little by its not quite a cop-out but still frustrating ending, which seems to be trying to satisfy a larger audience while still paying lip service to its indie base. It's wholly unsatisfying as a story resolution, but by that point you've likely realized you're watching to see Caplan, not to find out what happens to her character.