Your Sister's Sister, Lynn Shelton's whiney mess of a movie that so wants to be adored, is more like millennial trailer trash. This liquor-fueled, uneven banter of 30-something slackers, each more self-absorbed than the next, is 90 minutes of cramps that I shall not soon forget.
Shelton's film is the latest art-house entry in the so-called "mumblecore" genre--the label du jour tagged to low-budget, meandering talkfests that are more acting exercises than movies. Film pragmatism is nothing new--director John Cassavetes perfected it in the 1960s--and at its best, reality-based method acting can lay a thin membrane of reality over melodrama. But the banality of Your Sister's Sister is mind numbing, no amount of attractive actors or lush scenery (which are bountiful here) can rescue this crapfest.
The plot is more Penthouse than paradox: three young adults, two of them sisters, are entangled in a triad of sexual tension. The premise of crisscrossing two sets of siblings is as old as Shakespeare, but when only three of the four participate, you have much ado about shit.
Jack (Mark Duplass) is the slovenly brother of Tom, who is dead before the story begins (lucky him). On the anniversary of his death, Tom's once-girlfriend Iris (Emily Blunt) offers her family cabin to a still-grieving Jack for some alone time. When Jack arrives at the remote cabin on Washington's Puget Sound, he comes upon (and I mean that in the most literal way) Iris's sister Hannah (Rosemarie Dewitt), who has also isolated herself from reality.
Egocentricity fills the screen as the story morphs into something resembling a bad telenovela. But wait, there's more. Naughty hijinks ensue when Iris shows up to profess her new attraction to her dead boyfriend's brother.
Shelton's script abandons her actors in quicksand. DeWitt, who was so heartbreaking as the title character in 2008's Rachel Getting Married, is strapped to the underdeveloped role of bisexual Hannah. Blunt, who is pretty fabulous in so many films, including this year's underappreciated Salmon Fishing in the Yemen, attempts to grin her way through the thankless role of Iris. Duplass, as Jack, is the most ship-wrecked of the trio. We don't know whether to root for Jack or be reviled by his dick-for-a-brain behavior. All three deserve better.
It's a shame. Jack's back story, absent the slutty siblings, might have offered a good tale to tell. Somewhere along the way, Jack allowed the ghost of his brother to become too important in his life. But instead of examining the complexity of dealing with an unresolved specter, Shelton instead tosses this lost soul into a quite-icky sex comedy.
There's nothing cute about sleeping with two sisters, and there's good reason why they keep Penthouse behind the counter. It's trash. Your Sister's Sister commits an even greater sin: It's barely interesting.