Fact1: brother is married to American woman in Los Angeles, Fact2: Legion commanding officer travels arriving at French Embassy finding work on tramp steamer headed for U.S. Meanwhile, Fact3: Lyon 's desertion is ranked at low importance with LAPD, Fact4: Lyon arrives in New York City and travels to California to be with brother 's family, Fact5: Joshua uses prize money to give to Lyon 's sister-in-law in form of checks with Joshua claiming to be from life insurance firm
Output: Lyon Gaultier is a paratrooper in the French Foreign Legion, stationed in Djibouti, North Africa. His brother, who is married to an American woman in Los Angeles, is burned alive during a drug deal gone wrong and suffers thirddegree burns, dying shortly afterward. Lyon deserts his legion when he finds out they have been withholding letters from his brothers wife and ultimately refuse to let him see his dying brother. He steals a jeep and escapes through the desert, finding work on a tramp steamer headed for the U.S. Meanwhile, the Legion commanding officer also travels to the States, arriving at the French Embassy, where he is told that Lyons desertion is ranked at low importance with the LAPD, so he orders two of his own Legionnaires to do the job. Lyon arrives in New York City and travels to California to be with his brothers family. Along the way, he meets Joshua, a man who runs fights for money, and also learns that he cannot avenge his brothers murder, as he failed to identify his killers before dying. Tagging along with Joshua, Lyon meets Cynthia, who organizes underground fights for the rich elite and decides to sponsor him. Figuring that this would be the best way to earn the money his family needs, Lyon fights in noholdsbarred bareknuckle fights to finance the trip. Once they reach L.A., he tracks down his brothers widow, who is reluctant to accept financial aid, even though she obviously needs it, because she is angry with Lyon for deserting his brother years ago. This is when he finds out that his brother has already died. Joshua introduces Lyon in the fighting circuit as the titular Lionheart, derived from Lyon. Lyon continues fighting, and Joshua uses the prize money to give to Lyons sisterinlaw in the form of checks, with Joshua claiming to be from a life insurance firm her husband allegedly subscribed to long ago. Meanwhile, the two Legionnaires catch up with Lyon in Los Angeles. Lyon fights them off, but suffers a broken rib. Cynthia decides to take advantage of Lyons string of victories by stacking the odds in favor of a massive, brutal fighter named Attila the Hun, who has so far been unbeatable. Cynthia stacks the odds by smuggling a video of Atilla fighting poorly from one of his earlier bouts, which as expected fails to impress the oddsmakers. Cynthia later reveals Attilas true prowess to the Legionnaires, and she promises to deliver Lyon to them after he has been thoroughly humiliated and beaten. The Legionnaires agree to this, provided they can be in the audience. Lyons fight with Atilla is hampered by his broken rib. Atillas trademark deliberately withheld from Lyon is to let his opponent tire themselves out before viciously breaking them, often killing them in the process. When it appears Attila has won, Joshua begs Lyon to give up, revealing that they were both used by Cynthia. Joshua, for the best of reasons Lionhearts family, placed all of his own money on Attila as a form of insurance, as all the odds are against Lyon winning. Lyon, angered by this news, bounces back and summons up all his remaining strength to defeat Atilla, subduing but not killing him. While bookies sideline Cynthia demanding she pay up, the Legionnaires capture Lyon. They escort him back to the apartment, where they give him some time to say his goodbyes before being returned back to Africa, where he will be courtmartialed for desertion. Lyon tells his niece that he must go but to try to look for times when life can be good, which is emotional as she does not understand. However, just down the road, moved by the familys heartbreak, the Legionnaires decide to let Lyon go. They believe he has shown the Legions values of honor, determination and service to others, both during the fight and helping out the family, and wish him luck in his new life in America. Ultimately, Lyon is shown running back to a pleased Joshua and joyous family.