CinemaDope

Dreamboat

By Glenn Lovell

You can’t help but be skeptical of a supposedly fact-based maritime movie when the third name in the opening credits, after the two stars, is that of the f/x supervisor. Those of us who take our nature hikes/swims straight (minus digital trickery) immediately put up our guard, become wary. Memories of the waterlogged, phony-looking “The Finest Hours” and “The Heart of the Sea” bob to the surface.

Baltasar Kormákur’s “Adrift,” starring Shailene Woodley and Sam Claflin — and Visual Effects Supervisor Dadi Einarsson (“Everest,” “Gravity”) — proves a happy exception to this rule. Though some of the obviously fake camera moves pull us out of the moment, remind us that, yes, It’s only a movie, there’s enough here that’s authentic to make this lost-at-sea yarn required viewing for arm-chairs adventurers who live vicariously.

Indeed, in many respects this is the best of its kind since J.C. Chandor’s bracing “All Is Lost,” with a never better Robert Redford reviewing life choices from the deck of his crippled yacht.

Kormákur’s variation, like Phillip Noyce’s earlier “Dead Calm” with Nicole Kidman, stands apart by reminding us that wind-lashed females can be every bit as determined and resourceful as their male counterparts when it comes to tacking, patching and trimming the jib; they’re more than wooden figures adorning the bow.

Based on the ordeal of Tami Oldham Ashcraft, 24, and Richard Sharp, 33, who while sailing a luxury yacht from Tahiti to San Diego in 1983 were caught in a Cat 4 storm, this one delivers the goods in heart-pounding suspense and, at times, nauseating realism. The grim prospect of a slow death from exposure and starvation is ever present. Cinematographer Robert Richardson, who knows a thing or two about shooting under harsh conditions (see “Platoon” and “The Hateful Eight”), captures the dazzling allure of the South Pacific as well as its quiet foreboding. His extreme long shots say it all: we are completely alone, mere specs on an endless expanse of shimmering gray. Composer Volker Bertelmann contributed the classy symphonic score, which is used sparingly to punctuate without upstaging the unfolding drama.

The script, adapted from Ashcraft’s 1998 account “Red Sky in Mourning,” opens with Tami, a nasty gash in her forehead, regaining consciousness after the boat has been swamped by a monster wave. Fiancé Richard has been washed overboard with a dinghy. Hysteria becomes primal scream, then steely resolve to rescue her partner. Throughout, Kormákur skillfully flashes back and forth from mangled desk to the couple’s first meeting and courtship, inching ever forward to, about 80 minutes in, the Moment of Truth, that looming wall of water.

Where “Adrift” founders is in the relationship department. As written, Tami (Shailene Woodley) and her Brit boyfriend (Sam Clafin) are stereotypical free spirits who meet cute and form an instant connection. He’s a hopeless romantic, who, tired of pleasing others, dropped out of the Naval Academy, designed and built his own boat, and now chases “infinite horizons.” She’s a surfer-beach bum from San Diego with familiar personal baggage and zero interest in going home. He’s taken by her “bloke-like” fearlessness and impetuosity; she’s drawn to his soppy earnestness, his Byronic love of the sea. It’s straight out of “South Pacific.” We half expect Richard to break into “Younger than Springtime.”

Claflin, Finnick in “The Hunger Games,” is fine as the smitten, too cautious boyfriend, but Woodley, who was so good as George Clooney’s older daughter in “The Descendants,” always seems self-consciously “on,” whooping and posing like a shut-in on her first Spring Break.

But then, just as we’re about to succumb from a sugar high, Kormákur smartly comes about, redirects his narrative to the life-or-death struggle mid-ocean — and we give ourselves over to one of the year’s more exhilarating rides.

ADRIFT ✮✮✮ With Shailene Woodley, Sam Claflin. Directed by Baltasar Kormákur; scripted by Aaron Kandell, Jordan Kandell, David Branson Smith from book by Tami Ashcraft, Susea McGearhart. 96 min. PG-13 (for violent storm effects, gruesome makeup, chaste nudity)

Lovell, former movie critic for the San Jose Mercury News, teaches film studies at De Anza College in Northern California. He has written about film for Variety, the L.A. Times and, most recently, the Boston Globe.