This lax sequel to 2004’s “National Treasure” brings back Nicolas Cage as Benjamin Franklin Gates tracking arcane clues leading to ancient treasure. Cryptographer as action hero. Hermeneutics as high concept. Last time it was a secret gold to fund the American Revolution. This time it’s secret gold to fund the Confederacy. Director Jon Turteltaub, and writers Cormac and Marianne Wibberley, can continue this franchise until they run out of American insurrections and assorted military adventures calling for secret backers, off-the-books treasure and maps on aged parchment. Back on the case is Gates’ girlfriend Abigail Chase (Diane Kruger), Gates’ sidekick Riley (Justin Bartha) and Gates’ dad Patrick (Jon Voight). Last time they kidnapped the Declaration of Independence to decode a secret map drawn on the back in invisible ink. This time they kidnap the President of the United States (Bruce Greenwood), who studied architectural history at Yale, to get the secret call number in the Library of Congress and a secret combination to unlock the secret book where presidents write down America’s biggest secrets. Conspirators in past centuries, including the Queen of England, set up trans-Atlantic chases and invent enigmas for no other reason than to give their erudite descendants puzzles to ponder. And again, gold is hidden in subterranean caches designed to kill interlopers yet offer them escape routes. In the first installment, Gates peers at a dollar bill and pronounces: “These symbols are telling us something.” That film’s $347 million gross told producer Jerry Bruckheimer that a sequel would lead to more dollar signs if not symbols. With Helen Mirren, Ed Harris, and Harvey Keitel cashing checks. (Bill Stamets)