Making films about horrific events will always be tricky. How soon is too soon? If you’re dealing with actual victims, how personal is too personal? Conversely, if you’re approaching the event from a historical but fictional standpoint, how much leeway should a filmmaker be granted?

The makers of The Impossible confront all of this and more with their film. It depicts one family’s struggle after being caught in the 2004 Indian Ocean tsunami that hit Thailand, among other countries. Based on a Spanish family, they have been switched to British for the purposes of the movie, led by Maria (Naomi Watts) and Henry (Ewan McGregor).

The film is one big survival tale, as Maria and her son Lucas (Tom Holland) are separated from Henry and their two other sons when the initial tsunami wave hits. As you might expect from such a devastating force, once the horror starts, it rarely ebbs. The wave of water isn’t even the half of it; it’s the resulting destruction, the lack of resources and the desperate search for loved ones that makes things close to unbearable.

There are many elements that make The Impossible a great film, but first and foremost is the depiction of the tsunami and the aftermath itself. How director J.A. Bayona (The Orphanage) and his crew so convincingly portrayed everything in the film is a question of movie magic to which I’m not sure I ever want to know the answer.

I just know that every component felt terribly real, from the overwhelming intensity of the water to the mind-boggling vastness of the ruin to the grimy conditions of the hospitals and other shelters. If ever a film deserved Oscar nominations for visual effects, art direction and cinematography, this is it.

But of equal importance is the acting. A great and moving story like this is nothing without capable actors to guide it through, and all of the principals are more than up to the task. Watts deserves all the accolades that come her way, as her character’s journey is as harrowing as any in recent memory. Watts doesn’t strike one false note throughout, a testament not only to her acting but her endurance.

Holland is equally as good, an impressive feat for a novice film actor. He literally and figuratively has to carry Watts for much of the film, creating an emotional bond that’s unbreakable. McGregor isn’t given quite as many dramatic scenes as Watts and Holland, but the moments he does get are some of the most raw and truthful ones in the film.

The only missteps the film makes are minor, including a few continuity errors and a tendency to amplify drama when playing things straightforward would have been just as effective. But Bayona and screenwriter Sergio G. Sanchez keep those incidents to a minimum, allowing the sheer emotion of the story to shine.

There are, of course, two other questions that could color your view of the film. One, why did two Spanish filmmakers change the nationality of the family from Spanish to English? Two, why tell the story of a family on vacation when so many local people were affected much more?

The answers to those lie in the vagaries of the film community, a topic which could be discussed from here until next Christmas.

All most of us can confront is the story with which we are presented, and in that respect, The Impossible is close to masterful. It is an emotional wringer of a film that’s difficult to bear, but it’s well worth the effort.