Kelley Quinn is the owner of Nantucket's Winter Street Inn and the proud father of four. Patrick, the eldest, is a hedge fund manager with a guilty conscience. Kevin, a bartender, is secretly sleeping with a housekeeper named Isabelle. Ava, a school teacher, is finally dating the perfect guy but can't get him to commit. And Bart, the only child of Kelley's second marriage to Mitzi, has recently shocked everyone by joining the Marines. As Christmas approaches, Kelley is looking forward to getting the family together for some quality time. But when he walks in on Mitzi kissing Santa Claus, utter chaos descends.