Plot
Soon after the Great War, Major William Foster (Gene Hackman), an American commander in the French Foreign Legion, suffers the haunting memories of leading an army of more than 8,000 men and watching them slowly get whittled down to just 200. He has suffered alcoholism as a result, and his only friend is his faithful sergeant, Triand (Rufus).
Foster arrives in Paris to assume a new command and takes the legion to Rif in Morocco to re-establish French authority, as the Bedouin and Berber tribes have begun to revolt against French rule. Foster is also ordered to escort archaeologists from the Louvre, who are uncovering an ancient city near Erfoud that was buried by a sandstorm 3,000 years ago. The site is the final resting place of a Berber saint, known to the French as "the Angel of the Desert". Foster was specifically chosen for the assignment as he is the only French officer alive who served in Morocco before the war. He had helped to develop diplomatic ties with the tribes by negotiating with El Krim (Ian Holm), the de facto leader of the scattered Rif tribes. One condition of peace was that the French cease all archaeological expeditions without the tribes' approval.
Foster receives fresh Legion recruits for his assignment. Among those who volunteer willingly or unwillingly is "the Gypsy" Marco Segrain (Terence Hill), a charming jewel thief famous for a three-year crime spree on the Riviera before getting arrested. Gypsy befriends three other recruits: the Russian giant Ivan (Jack O'Halloran), formerly a member of the elite bodyguard of the deposed Russian imperial family; "Top Hat" François Gilbert (André Penvern), a fashionable man and musician who lacks the physical traits needed in a soldier; and Frederick Hastings (Paul Sherman), a romantic young English aristocrat who longs for the days of the Great War.
The four friends are soon disillusioned by the harsh realities of life in the Legion, including heavy physical labour, little food and water and scorching heat. A fatal fight breaks out among the men while they travel to Morocco over an insult to Foster's honor, to which Triand takes exception.
Foster does not hesitate to discipline his men harshly, especially the insubordinate Marco, but ensures never to go too far and actively works to make sure his men are fit and ready for the hardships ahead. During the voyage, Marco charms one of the accompanying archaeologists, Madame Picard (Catherine Deneuve).
During their journey, the train carrying the Legionnaires and the archaeological team is stopped by El Krim and his men. El Krim greets his old friend Foster but also declares that Morocco belongs to his people and that the French are no longer welcome. El Krim gives a "gift" to Foster to take back to the Premier of France: the archaeologists of an earlier dig who have had their eyes and tongues gouged out and been subjected to exposure. He warns Foster to turn back while he still can. In response, Foster shoots the two mutilated archaeologists to end their suffering. One of them is afterwards revealed to have been Madame Picard's father.
Upon reaching their fortress, Foster puts the men through brutal and unforgiving training exercises. Top Hat collapses during a march and is left to die of thirst but manages to return to camp and ultimately commits suicide rather than endure any further abuse. Later, at the digging site, Hastings is kidnapped on guard duty and is tortured to death by a tribal raider, whom El Krim excuses as being merely overzealous. Marco retaliates by killing his friend's murderer. Instead of disciplining him, Foster defends him by using the same excuse, and El Krim accepts it.
Eventually, the tomb of the Angel of the Desert is found, and her golden sarcophagus is excavated. Foster offers it to El Krim as a token of peace, but El Krim rallies the warriors of the Bedouin tribes to slaughter the Europeans. The well-trained Legionaries shoot down hundreds of tribesmen but are eventually overrun. Ivan is killed, but Marco fights on and single-handedly kills multiple enemies trying to outflank his unit. When Foster is finally shot dead, El Krim immediately calls off the fight, sends the surviving legionnaires "to tell the world what happened" and allows them to take Foster and the remains of their fellow soldiers back home.
The two endings are the television version, which ends with Marco taking up Picard's offer to desert the Legion and leave with her, and the theatrical ending, which shows Marco, who was promoted for his bravery in battle, staying behind, training more Legionnaire recruits and welcoming them by reiterating Foster's earlier warning: "If the Legion doesn't get you, the desert will. If the desert doesn't, the Arabs will. And if the Arabs don't, then I will. I don't know which is worse."
Additional scenes
In the television version, several scenes were used that were not included in the theatrical or in the video/DVD versions of the film. One pivotal extra scene occurs after the excavation work has commenced, and two of the legionaries, both of them German recruits, are found to have deserted. The sadistic second-in-command of the company, Fontaine, and his equally vicious crony, the corporal, lead a patrol to capture them. They catch up with the two Germans, and Fontaine orders the patrol to shoot them. The noise attracts a large group of Bedouin tribesmen, and disregarding the warnings from his men, Fontaine orders his men to open fire, igniting a battle. The corporal is shot dead, and Fontaine breaks down in fear and kills himself. Marco displays his courage and natural flair for leadership by rallying the survivors of the patrol and successfully beating off the attackers.
In the video release, that scene was omitted, but brief shots of Fontaine and the corporal were taken from this scene and edited into the climactic battle at the digging site, which makes it appear that both men died there instead.
