Barr's standalone thriller is an unexpected treat featuring 68-year-old widow Rose Dennis, who finds herself drugged and confused in the exclusive facility Longwood Memory Care Unit as an Alzheimer's patient. Completely befuddled when she overhears voices suggesting her demise at the end of the week, Rose plans her escape. Emerging from the brambles of a hedge around the hospital, Rose is spotted by two boys who offer her water but immediately return her to her captors.

Struggling through the fog of medication, the unwilling patient pretends to take her pills, her growing clarity allowing the lucidity necessary for a new escape plan. From the first page, Rose is a seductive protagonist, burdened by the recent tragedy of widowhood but revealing glimpses of a determined, energetic personality with a gift for irony, searching for humor in the most dire of circumstances. Aware of her surroundings and potential danger, Rose heads directly to the home of her 13-year-old granddaughter, Mel, a willing accomplice in evading the searches for the escapee. While the circumstances of Rose's predicament could be disturbing for some reader's, Barr's prose creates not a victim but a survivor, a spunky, clever woman thrust from a happy marriage and a new home to the loss of a beloved husband and confinement in an Alzheimer's unit.

The protagonist is no pushover but a resourceful, wily woman on the run with the aid of a granddaughter tuned into the digital perks in the age of Uber. When Rose breaks into the home she shared with her husband, she makes contact with her reclusive sister, Marion, who flatly rejects the label of "hacker" but is proud of her computer skills when Rose needs specific information. Exhausted by her adventure as an escapee from the hospital, surrounded by packing boxes, Rose falls gratefully into her own bed, dressed in familiar clothing and freshly showered.

She wakes to the sound of an intruder slowly creeping up the stairs to her bedroom door. Narrowly missing disclosure by climbing out a window, the stranger makes clear his intention to find his victim in a harrowing episode of cat-and-mouse. Rose eventually confronts her pursuer while clinging to a skylight on the roof, the enraged man inching toward her with a knife between his teeth and menace in his eyes. Events unfold apace, Rose prepared (with Mel's assistance) to execute a daring plan to save another potential victim of the deadly Alzheimer's unit. And she needs to learn the identity of the person behind her confinement, who may even be a family member who has decided Rose is more valuable dead than alive. With Mel's help and Marion's research on the computer, Rose proves a formidable adversary, plunging bravely into the dark secrets of people who prey on the elderly, including herself, seeing them easy, helpless targets.

Barr captures the wild glory of a woman who embraces life at every stage, unmoored by the realization that "What she forgot is frightening. What she remembers is deadly." Barr's wonderfully inventive style fills her novel with humor, compassion and energy, a paean to women and the bonds of family. What Rose Forgot breaks all the rules but, like its protagonist, refuses to be defined. Small of stature, helpless against more powerful foes, Rose strikes a blow for the refusal to fade quietly into old age. Perhaps the plot is a bit implausible, but Rose's adventure in a world that considers her disposable is a celebration of life from sunrise to sunset.