MacDonald marries domestic disharmony with contemporary life in 2011 Limerick, Ireland, and the Upper West Side of New York City, when two families exchange homes for a week’s vacation. Strangers until the exchange, the O’Briens and the Harveys meet online, sending photographs and pertinent information prior to the agreed upon dates. Both families are in need of a break, Hazel Harvey grappling with a critical decision about the future, Mannix O’Brien facing the consequences of chronically foolish decisions, happy to have a vacation--and respite--in New York City with his family. An agreement is reached, each family assembling belongings, anticipating a change of scene in another country. The idea of a completely different landscape, a much-needed fresh perspective becomes instead a nightmare that alters each family dynamic, exposing a history of petty lies and furtive secrets.

Oscar and Hazel Harvey reside in a luxury apartment inherited from Oscar’s parents. Their uptown address is no panacea for the burden Hazel carries, her only escape the pages she fills daily in her journal. In spite of Oscar’s disapproval, Hazel has opted to teach in a school for disadvantaged and difficult students, often the last chance before they are swallowed up by the system. Both stubborn and terrified in an exacting position, Hazel won’t give up on these kids, Oscar unable to dissuade her from her mission. Hazel looks forward to the exchange, holding an ugly secret close and putting on a happy face as she, Oscar, nine-year-old son Elliot, and 12-year-old daughter Jess return to the city of her birth, where she expects to draw strength from the familiar streets of her childhood.

A busy working mother, Kate O’Brien has just turned down an opportunity for promotion in lieu of spending time with eight-year-old son Fergus and 12-year-old Izzy. On the autism spectrum, Fergus thrives on consistency, predictability in his routines, Izzy fading into the shadow of her brother’s needs but fiercely protective of him. Mannix O’Brien is a volatile, energetic man, a slight rogue who often requires a good deal of his wife’s forgiveness and compassion. Manny’s younger brother, Spike, injects tension into the drama when he appears on the eve of the trade, his murky business issues intruding on the preparations for the trip, though he promises to pick up the Harveys from the airport and explain the idiosyncrasies of the house to the newcomers.

The home swap accomplished, MacDonald’s two families plunge into exploring their new environments. Oscar watches Hazel for signs of stress, while Kate notices Manny’s distraction and constant need to check his cell phone. Tragedy arrives without fanfare near the end of the week, galloping in on a big black steed and shattering whatever semblance of normalcy these couples have managed to provide their children. One terrible act tumbles row after row of careful construction, the lies that shield a husband from his wife’s wrath, a woman’s stoic façade hiding a growing terror that renders her helpless. The tension builds in broad strokes, from Limerick to Manhattan, the denouement--when it finally arrives--both shocking and brutal, the terrible consequences of minor lies and obfuscations grown deadly.