The opening moments of “Adrift” announce that we are watching “a true story,” which should by rights permit me to discuss a few matters freely. Recorded facts — even when they concern people who are not especially well-known — cannot really be spoiled, and any good movie that claims history as inspiration should be able to withstand even the most detailed of plot summaries.

Certainly it gives away nothing to note that this lovers-in-peril drama was adapted from Tami Oldham Ashcraft’s 2002 memoir about how she and her fiancé, Richard Sharp, set sail on a 4,000-mile journey from Tahiti to San Diego, only to find themselves in the path of a devastating Pacific hurricane.

Yet having seen the movie, which compresses a traumatic 41-day ordeal into a swift, economical 96 minutes, my instinct is to veer toward caution. Not because the details of Oldham Ashcraft and Sharp’s ill-fated 1983 voyage are unknown but because “Adrift” — the latest in a string of visually persuasive, dramatically spotty survival pictures directed by Baltasar Kormákur (“Everest,” “The Deep”) — has twisted a few of those details in service of its own clever narrative agenda.

There’s nothing inherently wrong with this. A biographical drama should be judged by a higher standard than strict historical accuracy, and some of “Adrift’s” liberties are canny and effective. The movie opens after the hurricane has already come and gone, leaving a dazed, injured Tami (Shailene Woodley) to sift through the partial wreckage of the yacht. We share in her disorientation as she climbs her way to the deck, calling out frantically for Richard (Sam Claflin), and finds that the storm has severely damaged the boat and blown it far off-course.


Cue the first of several flashbacks to happier days. We see Tami, a twentysomething wanderer from California, arriving in Tahiti, supporting herself with odd jobs cleaning and repairing boats. She quickly meets and falls for Richard, a sweet, funny and similarly free-spirited English sailor in his mid-30s. The two bond above and below deck, dreaming about their future travels together and swapping troubled family histories. The title of “Adrift” might refer to an emotional state as well as a physical one, shared by two young people who find in each other a sudden antidote to years of aimless, free-spirited living.

There’s an authentic poignancy to Tami and Richard’s connection, buoyed by the actors’ sweet, unforced chemistry. As seen in her best performances (in “The Descendants,” “The Spectacular Now” and the HBO miniseries “Big Little Lies”), Woodley has a gift for conjoining inner strength and vulnerability until the two are all but indistinguishable. Her flinty American prickliness finds both a loving embrace and a gentle foil in Claflin’s soft eyes and mellow, British-accented charm.

It’s the primacy of that bond that keeps both Tami and the movie going even after disaster strikes and the long, arduous work of survival begins. Hours after the storm passes, Tami is relieved to see Richard alive but unconscious and seriously wounded. It thus falls to Tami, less experienced but no slouch in the sailing department, to get them back on course, using little more than a sextant. Water and rations are scarce; after the two gorge themselves on a precious jar of peanut butter, Tami, a vegetarian, is forced to make do with tinned sardines and a few unfairly maligned cans of Spam.

Shailene Woodley and Sam Claflin star as a couple “Adrift.” (Kirsty Griffin / STXfilms )


The conventions of the lost-at-sea genre are all here and accounted for: the grim dressing and redressing of wounds, the external manifestations of constant hunger, thirst and exposure to sunlight, the despairing on-screen markers of time slowly but surely passing (“5 days adrift … 8 days adrift”). What the movie lacks is the patience and slowly enveloping power of a drama like “All Is Lost” (2013), which cast a shipwrecked Robert Redford in a one-man existential procedural. In contrast with that movie’s present-tense linearity, “Adrift” keeps doubling back on itself, shuttling convulsively between time frames.

The benefits of this accordion-like structure are obvious, particularly from a screenwriter’s perspective. (The script was written by Aaron Kandell, Jordan Kandell and David Branson Smith.) A scrap of dialogue can bring back a flood of relevant memories; an image of the present can trigger an elegant transition to the past. The details of how Richard and Tami decided to embark on their crazy expedition in the first place snap intriguingly into place like puzzle pieces. The storm itself provides a hell of a climax, an impressive demonstration of how the most restrained visual effects can also be the most terrifying.

But most of all, perhaps, the rapid-cutting structure provides us with regular bursts of relief, steady distractions from the horrors of long-term deprivation — a relief that Oldham Ashcraft and Sharp, of course, were cruelly denied.

It’s easy, maybe too easy, to watch “Adrift,” because the filmmakers keeps letting their audience off the hook. What seems at first like an ingenious and surprising dramatic strategy feels, by the end, like an evasion on the movie’s part, a refusal to grant its subject the unflinching honesty it deserves. A true story it may be, but no one should mistake it for a truthful one.


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‘Adrift’

Rating: PG-13, for injury images, peril, language, brief drug use, partial nudity and thematic elements

Running time: 1 hour, 36 minutes


Playing: In general release

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justin.chang@latimes.com


@JustinCChang