With the mediocre Adrift, Baltasar Kormákur continues his turn from the fascinating Icelandic police thriller Jar City to fact-based man vs. nature movies (The Deep; Everest) — with room for the odd Mark Wahlberg dud (Contraband; 2 Guns), of course.

Told in mostly successful chopped chronology, the film centers on new lovebirds Tami Oldham (Shailene Woodley) and Richard Sharp (Sam Claflin, Their Finest), whose sailboat voyage from Tahiti to San Diego is interrupted by a violent storm that critically injures him and tests her aquatic knowledge.

Though better than the repetitively grisly lifeboat portion of In the Heart of the Sea, the story validates the dramatic limitations of oceanic survival movies and isn’t helped by the sense that Woodley grunts and wails in desperation more often than she talks.

The path to disaster, however, is Adrift’s best section, one not just of believable romance but beautiful jungle scenery, crisp open-water scenes that capture the thrill of sailing and an exquisite single-take where the camera operator leaps in tandem with Richard off a rock face and into a pool, where he frantically searches underwater for the unseen Tami.

This preamble isn’t quite enough to warrant deep attachment to our heroes when extreme hardships arise, but it’s nice while it lasts and every once in a while syncs up nicely with words or actions in sudden jumps to or from the future.

Grade: C. Rated PG-13. Now playing at AMC Classic, Biltmore Grande and Carolina Cinemark

(Photo: STX Entertainment)