'Sister': Not your mother's romantic comedy

Mark Duplass, left, Emily Blunt and Rosemarie DeWitt star in the graceful and charming 'Your Sister's Sister.' (Credit: By Steven Schardt, IFC Films)

So many movies try to capture human relationships and fail miserably. A few come close. Your Sister's Sister nails it with grace, humor and winning charm.

The authenticity is helped immeasurably by a wholly unpredictable, unconventional and always captivating story, written and directed by Lynn Shelton. Although the plot would fall broadly under the category of romantic comedy, this is nothing like a standard-issue Hollywood rom-com. Shelton writes dialogue that people would actually utter and draws performance that feel incontestably real. Romantic, funny, surprising and thoroughly involving, Your Sister's Sister is the rare film you give yourself over to completely.

The film opens with Jack (actor/filmmaker Mark Duplass, wonderfully funny in this role) at a party commemorating the one-year anniversary of his brother's death. He's a mess, and initially comes off as boorish. But because of Shelton's brilliant dialogue and Duplass' natural performance we understand his underlying pain and inherent decency as he connects sincerely with his best friend Iris (a terrifically engaging Emily Blunt).

"And how did that go for you?" she quips, after Jack alienates a group of his brother's friends.

Worried about her aimless and depressed friend, Iris goes into no-nonsense, protective mode, sending him off for a stay at her family's secluded island house. He needs to ride his bike there, clear his head and soak up the scenic natural beauty, she instructs.

And so he goes.

When he arrives at the house, situated idyllically in the Pacific Northwest, he's surprised to find that someone is already there. It's Hannah (Rosemarie DeWitt), Iris's older sister, who has unexpectedly come to stay following a romantic break-up.

After their initially awkward meeting, the two connect. Personal revelations are hinted at, but more is left out.

The following day Iris shows up, feeling badly about sending Jack off so summarily. As portrayed by Blunt and DeWitt, theirs is a connvincing depiction of sisterly bonds. The easy affection among all three of the characters grows, but so do several concerns.

Each of the characters is multidimensional and complicated, and the film goes in the sorts of unexpected directions normally reserved for the best novels.

Your Sister's Sister feels like a new flavor of fruit, one with a complex taste that is never artificial, bland or too sweet.

By the conclusion of this gently moving film, we feel we have come to know the people involved and understand their emotions. We feel for their hopes and worries and we're better off for having met them.

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