During a mission in the 1942 American invasion of Africa, Charlie, a young paratrooper, is briefly separated from his squad after making his jump. When Charlie is reunited with Cowboy, a daring member of his squad, the men consider ambushing a German machine gun nest nearby. Because they are under continual fire, however, Cowboy tells Charlie that they should retreat and search for the rest of the squad while the Germans reload, but Charlie does not hear him. While Cowboy dashes away, Charlie advances alone, only to find his gun is empty when he has clear aim at the Germans. As he reloads, the Germans withdraw and Charlie is confused to find himself on his own. Meanwhile, Cowboy locates other squad members including the lieutenant, the sergeant, a genial soldier nicknamed Pigpen and Cowboy's childhood buddy, Ace Mason. After Cowboy reports that Charlie froze in fear when he advised that they move on, the lieutenant reveals they have been ordered to wrest control of the mountain from the Germans, whose control center is a hillside dugout. Planning to make a silent attack, the men creep toward the Germans' stronghold, only to spy a German soldier exiting the dugout pulling a wire fuse down the hill. Ace circles around and stabs the German to death, but not before the soldier lets off a round of gunfire. Hoping to convince the Germans that their comrade has survived, Cowboy volunteers to dress in the dead soldier's uniform and attack the dugout. The plan works as intended, and the Americans run happily toward the dugout, their arms raised mockingly as Cowboy appears, still holding his gun. Charlie, approaching from the opposite hill, spots the men and, believing his squad is being taken prisoner, shoots and kills Cowboy. After Charlie rejoins the shocked men, he is horrified to realize his error and the men, especially Ace, are bitter and hostile despite the lieutenant's acknowledgment that the shooting was an understandable mistake. Later, Ace threatens to kill Charlie on their next jump. Soon after, the paratroopers are dropped over Sicily during bad weather that causes a staggered jump. On the ground, the men grope about in the dark searching for one another. Charlie comes under fire several times until he meets up with the lieutenant and another soldier named Mike, and wonders if Ace was attempting to follow through on his threat. At daybreak, as the group nears a farm, the lieutenant receives radio orders to set up an observation station to report Germany activity, while the sergeant and Pigpen befriend the farmer and his pretty daughter. That night in the barn, Charlie confides in the lieutenant his distress that the men continue to believe that he killed Cowboy intentionally. The lieutenant tells Charlie he can transfer to another service branch if the pressure is too great, but Charlie refuses. He confesses that he has been a failure most of his life and joined the paratroopers, the most dangerous service he knew, to prove that he could finish something he started. The following afternoon, as Pigpen is distracted from guard duty by the sergeant's flirtations with the farmer's daughter, a German advance patrol drives onto the farm unnoticed. As a fierce gun battle ensues, the sergeant, who is at the back of the house, concocts a fire bomb that kills most of the Germans. When the lieutenant and Pigpen are trapped under fire at the front of the house, the lieutenant rushes the house with a grenade, but stops when the Germans threaten to kill the farmer and his family unless the Americans surrender. Ignoring Charlie's attempt to help, Ace and the sergeant take the German motorcycle and sidecar and surprise the Germans, rescuing the others. As the war continues, Charlie remains preoccupied by the disdain of his comrades. The paratroopers then receive orders to assist in the invasion of Salerno, where they must locate a German tank division before it reaches the invading forces on the beach. Charlie and Art, another trooper, are given a generator and radio and are ordered to set up communications upon landing. Landing in a dangerous area under continual fire, several paratroopers are killed. When the lieutenant and Art spot the German tanks, Art goes in search of Charlie, who has the generator, but runs across a mined road and is killed. The lieutenant does not hear Pigpen's warning about the mined road and is wounded when he goes after Art to secure the radio. The lieutenant calls to the men that the radio is undamaged and they must find Charlie and retrieve the generator. Several men are wounded or killed trying to get to Charlie, who became entangled in a tree as he neared the ground. The sergeant makes it to the tree, but is wounded cutting Charlie down. Charlie revives and is shocked when Ace and Pigpen die in front of him trying to reach the generator. As the sergeant and Charlie head toward the lieutenant, the sergeant cautions Charlie about the mined road and declares he will crawl ahead and clear the way with grenades. Charlie points out the sergeant's wounds will not allow him to throw the grenades and gives him the generator. With the sergeant and lieutenant providing covering fire, Charlie clears half of the mined road but when he throws his final grenade, it fails to detonate. With only twenty feet to go, Charlie realizes he must sacrifice himself to clear the path and runs across the road, detonating the last mine. The sergeant safely reaches the lieutenant with the generator and as the men contact air forces with the tank corps location, the lieutenant salutes Charlie for successfully fulfilling his mission.
