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.

Nina Frisk is a flight attendant who loves flying. She is happy above the clouds, far away from her dysfunctional family and superficial love life. But then one day Nina meets Marcus and his son William, and falls helplessly in love. For the first time ever in her life, Nina begins to long for a family of her own. But Nina soon discovers that life on earth can be just as turbulent as in the sky.