I'm still trying to wrap my head around the historical premise for this Indiana Jones knockoff—that during the Civil War the Confederacy loaded an ironclad battleship with gold coins, piloted it across the Atlantic, and beached it in the middle of the Sahara. As Jefferson Davis used to say, whatever. Hunky Matthew McConaughey and wisecracking Steve Zahn, explorers for a U.S. aquatic-salvage agency, persuade their dyspeptic commander (William H. Macy) to let them mount a search mission for the lost treasure, and along the way they pick up a babe doctor from the World Health Organization (Penelope Cruz) who's tracking a strange malady. A team of four screenwriters adapted a novel by Clive Cussler; the first-time director is Breck Eisner (Michael's son). PG-13, 124 min.