It's remarkable how much you can class up a Jerry Springer-esque conflict if you cast its characters as thoughtful, funny, lovably flawed people.  Your Sister's Sister takes a premise worthy of a "Jerry" chant and imbues it with warmth and compassion through charming performances by its lead cast.  However, the heavy reliance on dialogue to the expense of other cinematic elements leaves the film only as good as its conversation, and also makes the audience feel like voyeurs who are intruding on the characters' personal lives.

Jack (Mark Duplass) is still a mess a year after his brother's death.  Iris (Emily Blunt), who was previously in a relationship with his brother, invites Jack to go to her family's cabin where he can clear his head.  When he reaches the cabin, head-clearing is not on the menu when he unexpectedly finds Iris' sister Hannah (Rosemarie DeWitt).  Hannah is at the cabin to get away from her recent break-up with her longtime girlfriend, and the two commiserate over heavy drinking.  Hannah's lesbianism turns out to be no match for the combined forces of Liquor and Cuddly Duplass Charm, and she ends up sleeping with Jack.  The two must then work to cover up their tryst when Iris decides to drop by so that things don't get "weird."

First off: these people are in dire need of a cabin-use schedule.  Unexpected arrivals aside, the relationships between the main characters become even more complicated when Iris reveals to Hannah that she has feelings for Jack.  If you remove the characters from the situation, it would fit perfectly in an episode of a trashy daytime talk show.  Your Sister's Sister dodges that problem by making its characters likable and sympathetic.  No one in the movie is trying to hurt anyone else.  When Jack and Hannah sleep together, neither has any idea that Iris has feelings for Jack.  These are good people who have secrets not because it keeps the plot moving, but because they care about each other's feelings.

your-sisters-sister-movie-image-emily-blunt-rosemarie-dewitt-01

The relationships work because writer-director Lynn Shelton has clearly given her actors a lot of freedom to craft their characters, which is essential because the entire movie rests on its actors' shoulders.  Shelton takes a mostly point-and-shoot approach where characters have their conversations at a table or in a hallway and the writer-director chooses to use almost no music and make sure the cinematographer's most difficult task is to obey the 180° rule.

This is an actors' film and it wouldn't work if it didn't have three people as talented as Duplass, Blunt, and DeWitt in the lead roles.  The dialogue sounds semi-scripted but even if it's fully-scripted, the actors make the story and characters feel real rather than sensational.  They keep the drama intimate and honest as the story becomes increasingly outlandish.  The only time when the performances aren't enough is when the conversations run on too long or if there's nothing interesting to say.  At these moments, we stop being interested in the situation and start to question if we're just spying on these people.  There's a nature of voyeurism in all cinema, but we become more aware of it with Your Sister's Sister due to the presentation.

Your Sister's Sister isn't trashy because it isn't flashy.  It's restrained almost to the point where the direction feels lazy, but the low-key approach mostly adds a level of authenticity to the story.  The approach put a little too much weight on Duplass, Blunt, and DeWitt, but they're still able to make the movie into a nice mix of drama and comedy that keeps us invested in the characters instead of asking for a microphone so we can chastise them.

Rating: B

For all of our coverage of the 2012 Sundance Film Festival, click here. Also, here are links to all of my Sundance reviews so far: