Lynn Shelton’s Humpday (2009) is the kind of film that takes its’ high concept – two straight men decide to film themselves having sex – and develops it into something much more emotionally mature than any synopsis suggested. It also contained a lot of improvised dialogue and was thus associated with the ‘mumblecore’ movement. Your Sister’s Sister uses some improvisation in a similar way but has a slightly more conventional set-up: Jack (Mark Duplass), emotionally struggling a year after the death of his brother, takes up an offer from his friend Iris (Emily Blunt) to stay at her families’ remote cabin. Whilst there, Jack’s drunken encounter with Hannah (Rosemarie DeWitt), Iris’ sister, kicks off a revealing stretch of days.
What is immediately noticeable about Your Sister’s Sister is that not only does it have a more orthodox plot than Humpday, it also looks and feels familiar in a way that film certainly didn’t. This isn’t necessarily a criticism, definitely not a claim that Shelton has gone mainstream or anything like that, more an observation that this film fits right in with contemporary American independent cinema and the kind of things come out of Sundance.
Aside from the opening scene, containing a nice cameo from Mike Birbiglia, the entire running time of the film just has the three main characters talking, laughing and arguing. This means it relies a lot on the characters being believable and the performances anchoring the plot. The latter is thankfully realised well on screen, with DeWitt and Blunt rising above their forced backstory to depict an authentic sibling relationship and Duplass once again proving he is just as good at acting as he is at writing and directing with his brother Jay.
Are the characters believable? I’m less sure on this one. The love triangle between the three protagonists builds towards a set of reveals and an intense confrontation at the cabin. This scene works really well but the way all these plot strands are eventually resolved (treading lightly around spoilers here) feels forced in a way that nothing else in the film does, while the final shot may be the stupidest I’ve seen since last year’s Polisse. Your Sister’s Sister is a solid entry in Shelton’s body of work but I doubt it will ever be remembered as anything but a film with an interesting premise that didn’t know how to end so decided to play a trick on the audience that ultimately failed.