Thirty-two-year-old Jessica is newly divorced and has returned home to live with her parents whilst she puts the pieces of her life back together. But Jessica isn't the only one with problems, as her mother, Jean, has recently been diagnosed with dementia.

Shortly after Jessica's arrival, one of the neighbours falls to her death, in what appears to be a terrible accident. However, Jean claims that the woman was murdered by her husband and that she witnessed the whole thing.

With Jean's memory rapidly deteriorating, her family dismiss her story, believing Jean is confused. But when Jessica learns that the couple next door's marriage may have been in trouble, she begins to wonder if her mother did see something after all.

Jessica is determined to discover the truth, but soon uncovers much more than she bargained for...