US Marines unload a bulldozer from a docked ship, using tires as cushions for the dozer's metal tracks. Shots of Marines digging in and making bunkers in the sand. Interview with Staff Sergeant Marle, USMC, who talks about his unit's night mission of guarding checkpoints. Pan shot of area. A Marine guard searches a vehicle and checks driver's ID. (Note: Marle interview and checkpoint scene are tinted blue.)