British academics Loretta and Bridget run into Sandra, an old school friend at a book launch. Although Sandra appears to be gay and carefree, Loretta notices an undercurrent of tension while Sandra stays with her for a few days. Loretta is saddened to learn her friend was killed in a car accident, and comforts Sandra's estranged husband Tom, her daughter Lizzie, and emotionally disturbed son Felix. While doing so she becomes to believe the accident may not be what it seems, spurred on by the information a local policeman provides her.

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