On June 6, 1944, United States Army Private First Class Ronald "Red" Daniels of the 1st Infantry Division takes part in the storming of Normandy Beach with his squad, consisting of: Private First Class Robert Zussman, who is his best friend, Private Drew Stiles, Technician Fifth Grade Frank Aiello, Technical Sergeant William Pierson and First Lieutenant Joseph Turner. During the operation, Zussman is stabbed, keeping him on the sideline.
Zussman returns to duty to partake in Operation Cobra, where the Allied forces successfully push to reclaim the town of Marigny. The squad is ordered by Colonel Davis to conduct a joint operation with Special Operations Executive British officers Major Arthur Crowley and Vivian to intercept a German train carrying V2 rockets, near Argentan. Daniels and Zussman derail the train, before being escorted back to their squad by a French Resistance leader named Rousseau.
A week later, Rousseau and Crowley infiltrate a German garrison in Paris to retrieve explosives, in preparation of the squad's assault on the garrison. Midway, Rousseau kills SS-und Polizeiführer Heinrich, in retaliation for killing her family. The squad then successfully liberates Paris.
Two months later, the squad takes over a German-occupied hotel in the city of Aachen. They discover civilians inside the hotel, and Turner orders their evacuation, to Pierson's dismay. A young girl named Anna goes missing, and Daniels searches for her. German soldiers open fire on a truck carrying the civilians, killing Anna's older sister. Pierson sends the truck away without protection, creating a rift with Turner.
At the Battle of Hürtgen Forest, the platoon is ordered to take Hill 493. Turner splits the platoon into two groups; Pierson and Zussman are tasked with advancing towards the hill, while Turner and Daniels cover them until they can meet at the bottom. Turner's squad soon receives a transmission revealing that Pierson ordered an attack on the hill against Turner's orders. The platoon destroys an artillery position but the Germans counter-attack with a Tiger II tank. Daniels is knocked out trying to disable the tank, which is destroyed by tank commander Staff Sergeant Augustine Pérez. Turner is fatally wounded rescuing Daniels, and orders Daniels to abandon him while he covers the platoon's escape. Pierson becomes head of the platoon and makes Daniels his second-in-command, promoting him to Corporal.
At the height of the Battle of the Bulge, the platoon is surrounded by Germans. Daniels meets an African-American technician, Howard, who helps the platoon contact air support. The platoon captures several German soldiers and discovering that the Germans were ordered to destroy a bridge at Remagen, the last bridge over the Rhine. After destroying the explosives in transit, Pierson orders the platoon to attack a nearby air base to destroy the remaining explosives. The attack fails, resulting in Daniels and Zussman surrounded by enemy troops. Daniels is saved by Howard, while Zussman is captured and taken to a German POW camp, Stalag IX-B. In Stalag IX-B, Zussman is interrogated on his Jewish heritage by SS officer Metz, then beaten and sent to a POW labor camp. Daniels is hospitalized due to his wounds.
In the hospital, Daniels learns from Davis about the events that changed Pierson in the Battle of Kasserine Pass. After recovering, Daniels confronts Pierson in his tent and tears up his honorable discharge papers in order to rejoin the platoon. They successfully capture the last bridge over the Rhine. The platoon heads into Germany, liberating concentration camps in search for Zussman, eventually reaching the Berga labor camp, which they find abandoned. The camp's survivors were sent on a death march. Daniels finds and saves Zussman by killing Metz before he can execute him.
At the end of the war, Daniels parts ways with his platoon and returns to Texas, reuniting with his wife and newborn son. Daniels names his son Joseph Turner to honor the late lieutenant. He visits the grave of his older brother, Paul, who died fighting a wolf when Red was a kid. He places his Bronze Star medal on the grave, saying that his brother deserves it for teaching him to shoot.