A sequel to the classic war movie "The Guns of Navarone" in name only, the 1978 military mission movie "Force 10 from Navarone" opens with footage from the finale of the earlier film. The spectacular explosion of a German fortress built into a cliff on the Greek island of Navarone, however, concludes with a surprise to anyone familiar with the original film: actors Robert Shaw and Edward Fox now in the roles originally played by Gregory Peck and David Niven. A year later, they reunite as last-minute additions on a mission led by Colonel Barnsby (Harrison Ford in his first headlining role after "Star Wars") to destroy a bridge in Nazi-occupied Yugoslavia. Of course, they become essential as the unit loses members in a convoluted plot involving local guerillas, Nazi loyalists, and double agents. It's based on the novel by Alistair MacLean and directed by Guy Hamilton, a veteran of the James Bond features, but he fails to bring excitement or tension to the cliché-ridden script. Ford lacks the gravitas he would bring to starring roles just a few years later but Shaw and Fox effectively underplay their roles with wit and savvy. Carl Weathers costars as a stray who gets swept up in the mission and Bond veterans Barbara Bach and Richard Kiel play guerilla soldiers. It's ponderous and slow-moving but it does feature a visually impressive climax involving a dam explosion. Fans of MacLean's novels may be interested and Ford's billing may invite curiosity, but otherwise, it is inessential. Rated PG but features fleeting nudity and violence. Features commentary by film historians Steve Mitchell and Steven Jay Rubin. Not a necessary purchase. (S. Axmaker)