In December 2004, close-knit family Maria, Henry and their three sons begin their winter vacation in Thailand. But the day after Christmas, the idyllic holiday turns into an incomprehensible nightmare when a terrifying roar rises from the depths of the sea, followed by a wall of black water that devours everything in its path. Though Maria and her family face their darkest hour, unexpected displays of kindness and courage ameliorate their terror.

A struggling, indebted business man leaves his family immediately after Christmas to pursue a lucrative property deal that could solve all of his problems: buying foreclosed properties from banks at a fraction of their value, refi tting them for a minimum cost, and then selling them for a large profi t. He hires a local chauffeur for 24 hours to drive him around the mountainous area but, as night sets in and the weather worsens, the car is trapped on an icy road and the men face an uncertain fate.