Maria Bennett (Naomi Watts), her husband Henry Bennett (Ewan McGregor), and their three sons Lucas (Tom Holland), Thomas (Samuel Joslin), and Simon (Oaklee Pendergast) go on a Christmas holiday in 2004 to Khao Lak, Thailand. Arriving on Christmas Eve, they settle in and begin to enjoy the brand new Orchid Beach Resort. Two days later on Boxing Day, the massive 2004 tsunami inundates the area.
