"Your Sister's Sister" is a 2011 romantic comedy-drama film directed by Lynn Shelton. The story follows Jack, a man grieving the loss of his brother, who is invited to a remote island by his best friend, Iris, to help him heal. Upon arrival, Jack meets Hannah, Iris's sister, and the two share an unexpected night together. As the plot unfolds, the dynamics between the three characters become complicated, exploring themes of love, grief, and the complexities of relationships. The film is known for its improvisational style and strong performances.