Private detective Molly Murphy is back home in New York but suffering from depression after a miscarriage. An invitation to spend Christmas in a mansion along the Hudson River promises a welcome distraction for Molly and husband Daniel. However, their hosts seem rather tense and at odds with each other. Molly soon learns why: the couple's daughter disappeared shortly before Christmas several years ago and was never found. When a teenage girl claiming to be the missing daughter turns up on the doorstep, they all wonder if it's a Christmas miracle or a hoax.