Editor’s note: With Your Sister’s Sister beginning its limited roll-out this week, we thought it best to re-run Robert Levin’s sterling Sundance review of the film, already a Reject favorite. This review was originally published on January 28, 2012. Your Sister’s Sister is perhaps the most high-concept movie I saw at this year’s Sundance Film Festival, but it’s also one of the funniest and most heartfelt. Sometimes, a precise, discernible pitch really does have potential. And after this film and Humpday (in which two straight male friends decide to make an amateur porn film together), writer-director Lynn Shelton is fast establishing herself as one of the independent film world’s masters of such fare. Her new picture parallels pensive shots of the pristine, misty splendor of the Pacific Northwest with the story of three lonely, likable locals who are searching for happiness. Mark Duplass stars as the directionless Jack, struggling to cope with the recent death of his brother. Emily Blunt plays Jack’s best friend Iris, who is also his brother’s former girlfriend. To clear his head, she offers him the run of her family’s vacation home on a picturesque island off the Washington coast. Iris’s half-sister Hannah (Rosemarie DeWitt) is already there, though, looking to escape a trauma of her own: the end of a seven-year relationship. A drunken night with Jack leads to hilariously awkward sex and, eventually, serious consequences when Iris unexpectedly shows up the next day.