When Erin shoots the Captain in the ear at the end of the movie, she fires one round and then the gun clicks several times as she pulls the trigger. With that firearm, the Beretta 92F, the slide would be held open after the final round was fired to facilitate reloading. Had there been only "one round in the chamber" as the captain said, the trigger would not have clicked like it did because the slide would have been locked to the rear.