Your Sister’s Sister is a subtle and touching exploration of three people wrestling with various emotional issues. While seemingly familiar situations abound, there is enough uniqueness to the dialogue and roles to make it both compelling and highly entertaining. For a great part of the film, the characters are given free rein to openly explore themselves, what they feel and each other. What starts as a slightly convoluted set up ultimately delivers some surprisingly funny situations and heartfelt conclusions.

Jack’s brother Tom has been dead for a year. The reason why isn’t as important as the effect his life had on his friends. As they meet to have a service to celebrate his life, Jack (Mark Duplass) makes a speech about his brother that moves Tom’s ex-girlfriend, Iris (Emily Blunt), and to tell Jack he needs to sort his life out. Lending him the family cabin on a remote island, Jack sets out to spend some time alone to sort himself out. Upon getting there, he discovers Hannah (Rosemarie DeWitt), Iris’ sister, is already there having just broken off her long-term lesbian relationship. After an awkward meeting, the two settle in for the night, only to find they are both sleepless. Sharing a bottle of Tequila, they begin to share, however superficially, their problems and eventually wind up in bed together. In the morning, we find Iris standing at the door ready to spend the weekend. What follows is a series of farcical situations and revelations about each person, as the group as a whole. To say more would reveal too much of the film’s plot, ruining the revelations as they unfold.

Writer/Director Lynn Shelton wrote a basic screenplay with which the actors could improvise lines into in just 12 days. This approach allowed the three leads room enough to explore the situations without letting the dialogue become too stale from repetition and from getting too insipid trying to recreate spontaneity. Instead, it has not only created some nicely paced and well-timed dialogue, but some that is rather original and unique. This has the feel and the sensibility of a stage production rather than a film. Very close and intimate, we only have the three main characters to carry the story forward. What starts as a just plausible story quickly demands attention. Dealing with interrelationships that could have just as easily been at home in a drama, yet still manage to retain a gentleness about them that compels viewers to remain. The odd sexual aspect of this notwithstanding, there is a very compelling story unfolding here.

All three lead actors do a terrific job of breathing life into their characters. Duplass has a quite well developed understanding of comedic timing, not only giving some fantastic opportunities to his co-stars, but also stepping in with just the right word or gesture as it is needed. Blunt and DeWitt do present themselves as sisters quite convincingly, sharing soft intimacies, via looks and gestures, which siblings often enjoy. So too, do Mark Duplass and supposed best friend, Emily Blunt. This intimacy, so easy and natural, lends itself to making the film far less predictable than it might have been with lesser actors. The heartfelt way with which the revelations affect each character shows a maturity and depth not usually found in romantic comedies.

The spartan set, just a cabin in the woods on a remote island surrounded by the lush Pacific North-West as the background, serves the story well as the three struggle to come to terms with events, each other, and where, emotionally, to go next. The misty backdrop serves perfectly as a pause between scenes, allowing both the characters and the audiences a chance to absorb what has happened before proceeding to the next scene. Shelton never tries to cover any shortcomings of the film with fancy camera work or drown bad dialogue with loud music. So much more that the film focuses squarely on the drama the three main characters find themselves in.

Although the film does a terrific job of holding its attention to the drama unfolding, at times, it takes too long to get to the next revelation. The overall pace of the film is rather leisurely, so too are the sequences where the drama unfolds. It’s only once the main revelation have been given, then the film continues along in its leisurely pace without much to do. Being just an hour and half long, it feels like some footage was shot simply to reach that length. Once the final act is underway, it comes to a quick, although some may find it a bit heavy, Shelton was wise enough to leave the film with a positive ending.

A compelling mix of drama and humor, the spontaneous dialogue make for a much better film than the script would suggest. Anyone who enjoys dialogue driven comedy will enjoy this. It has a very satisfying finish to what starts as a pedestrian start, pulling the viewers in, in unexpected ways.

Recommended for couples looking for a smart romantic comedy.