The Impossible, a feature film based on the true account of a Spanish family’s experiences during Indonesia’s devastating 2004 tsunami, opens in darkness, with a dull roar. A calm blue ocean appears on the screen, then a plane screams into the frame as if catapulted from the projection booth. The start-stop motion jolts you into the churning, turbulent reality of The Impossible: in this cinematically recreated hell you’re going to see, feel and practically taste everything. The Impossible is technologically a marvel—the tsunami experience is harrowingly believable—but also emotionally rich. I hesitate to use this term, since it is so often equated with hokey, but The Impossible is life-affirming.
The noisy plane swooping over the ocean brings the Belon family to Thailand to spend the Christmas holiday on the beach. Henry Belon (Ewan McGregor) has a big job in Japan while Maria (Naomi Watts), trained as a doctor, stays home with their three young sons. Obviously, the Belons are no longer Spanish. Maybe Javier Bardem and Penelope Cruz weren’t available? Or maybe if you can get Naomi Watts and Ewan McGregor in your movie, you just make accommodations to the narrative. But it’s worth noting that of the estimated 282,000 people who died or disappeared in the tsunami, only about 1,000 were European, so the filmmakers were already starting from a point that could be contentious—what about all those dark skinned residents of the Third World who died or lost everything? Turning the Spaniards into blue-eyed blonde Brits only exacerbates the sense that this is a story about a very small, well-to-do segment of the victim pool.
(READ: Time’s list of 12 disaster movies that top Titanic)
However, The Impossible moves so fast that there’s scarcely any time to catch your breath, let alone dwell on such matters. Director Juan Antonio Bayona and writer Sergio G. Sanchez made a name for themselves with 2007’s elegant, slow-simmering horror film The Orphanage, but this time, they skip the tantalizing buildup. A typical Hollywood production would require someone to have an argument or misunderstanding prior to the wave hitting, just to heighten regrets and increase the sense of calamity. But the loving Belon family celebrates Christmas at their paradisiacal hotel, snorkel and dine by candlelight. Then in the morning, they hit the pool with books and balls.
The first warning they get of the oncoming wave is the clamor of departing birds. Maria is farthest back, and so endures the horror of watching her eldest, most independent son, Lucas (the fiercely good Tom Holland) struck first, then her husband and the two younger boys, 5 and 7. Watts’ primal screams as she clings to a tree are eloquent; how could anyone so small survive something so big? When Lucas is swept past her, alive, she lets go and follows him. It’s both a remarkable decision and completely understandable, not so much bravery as maternal necessity. When the waves finally subside, mother and son are battered and bloody but together. As they wade waist deep through an apocalyptic landscape, you feel them forming their own fierce little unit, one where all bets are off. “Is it over?” Lucas asks her. It’s clear that Maria has always had the answers, but she responds with terrifying uncertainty, “I don’t know.”
(READ: Remember how the world was supposed to end in 2012? TIME’s Richard Corliss on 2012)
There are saving graces, a can of Coke plucked intact from the wreckage (it’s always Coke, right? Remember The Road?), and the affections of a blonde boy the pair rescues, but Maria is badly wounded—Lucas nearly retches when he sees the flap of flesh hanging off her leg—and the movie doesn’t get any easier when the kindness of native strangers deposits them at a hospital. The wounded are zombies, coughing up unrecognizable, black objects, bleeding on the floor, too stunned to care. Maria could die of infection, or from whatever it was that punched a hole in her chest underwater. “You see that boy,” Maria tells the doctor attending her. “I’m all he’s got in the world.” If you’ve seen the too-revealing trailer for The Impossible, you know this isn’t true, and may think, as I did, that you know the whole story already. I was happy to be proved wrong; the entire family’s survival—Henry and the boys have their own heartwrenching challenges—provides its fair share of suspense.
Tsunamis are so unimaginable that the desire to see, to experience a Biblical wall of water for oneself, can run very deep (my own was the only reason to see Clint Eastwood’s off-key, Hereafter). The Impossible slapped some sense into my lust for disaster porn by enlightening me, from this safe but still palpable distance, on what it’s like to be keelhauled through populated areas. It left me shaken.
But also strangely bolstered, ready to go out there and be fiercely strong, like Maria. The Impossible’s lessons about disorientation and adapting to disaster—it’s hard not to love Maria when she binds her wound with tree branches—can be applied well beyond the tsunami scenario. As to the question everyone asks—how would I cope?—Watt’s Maria gives you something to aspire to. Even flat on a cot with an oxygen mask on her face, Watts is constantly connecting, with Lucas, with the injured around her and with the audience. As an actress she gave greatly in Michael Haneke’s 2007 Funny Games and in 2009’s Mother and Child, but in the former her performance was limited by the film’s single key of sadism and few saw the latter. She’s always superlative, but The Impossible is Watts’ best performance in years. The Impossible is full of great special effects, and I’m enough of a natural disaster junkie that I’d have seen the movie just for them, but in the end what I’ll remember is Maria’s face, her cries and her determination.
READ: TIME’s Mary Pols on Naomi Watts in 2009’s Mother and Child
SEE: Where Naomi Watt’s landed on Richard Corliss’s list of best performances in 2004