Spanish movie The Impossible is based on the true story of a Spanish family who were caught in the 2004 Indian Ocean tsunami as it hit Khao Lak, in Phang-nga. To reach a wider audience and enlist some big-name stars, director Juan Antionio Bayona, in collaboration with Spanish screenwriter Sergio G. Sánchez, turned the Spaniards into an English family: Henry (Ewan McGregor), his wife Maria (Naomi Watts) and their three boys. But The Impossible is otherwise shockingly realistic in its depiction of this tragic natural disaster. It’s also a gripping disaster movie where humanity, willpower and some incredible luck allow its characters to overcome impossible odds.

The family is celebrating Chrismas at a resort in Khao Lak. On the morning of December 26, a giant wall of black waves crashes onto the resort, destroying everything in its path. After the water recedes, Maria, who is badly injured, scrambles out from the debris with her eldest son, Lucas (Tom Holland) and another boy they’ve saved. As she drifts between life and death in the hospital, Henry, who has also survived, begins to search for his wife and son.

Bayona has made a great movie. The special effects bring what we’d previously only seen as shaky camcorder footage to chilling life. The sight of the wave blasting through the hotel and overrunning the countryside is breath-taking. The casting is stellar, too. The chemistry between McGregor and Watts would have been plenty to please us, but Tom Holland as Lucas really steals the show, with his raw portrayal of a boy thrust into terrifying circumstances. The Impossible makes us relive a trauma, one that was very close to home, but it also allows us to transcend it, by showing humanity at its best, full of hope, faith and bravery.