Kate and Mannix O'Brien live in Limerick, Ireland, in an unusual house they can barely afford. Their son Fergus is bullied at school, and their daughter Izzy wishes she could protect him. Kate decides her family needs a vacation, and is convinced her luck's about to change when she spots an elegant Manhattan apartment on a home-exchange website. Hazel and Oscar Harvey and their two children live in Manhattan. Though they seem successful and happy. Hazen has mysterious bruises, and Oscar is hiding things about his dental practice. They, too, need a change of pace, and Hazel has always wanted her children to see her native Limerick. The house swap offers a perfect way to soothe two troubled marriages. But when Oscar finds the bloodied body of a woman in the trunk of his hosts' car, it's just the start of what will be anything but a perfect vacation.