During the allied landing in Normandy two of the four Ryan brothers are killed. The third dies on New Guinea fighting against the Japanese. When the army administration realizes that the fourth and youngest brother is missing behind enemy lines in France, it atarts a rescue mission. A small group of soldiers under the command of Captain Miller, an experienced Ranger officer, is ordered to find Ryan and bring him home safely. It is supposed to be Miller's last mission before he will go on leave. Soon his soldiers began to doubt whether it makes sense to risk all of their lives to one single soldier.
When they finally find Ryan, the group has lost two its members. Instead of taking the opportunity to return home Ryan refuses to be led home. He is decided to stay with his unit which suffered severe losses. They are assigned to defend a bridge at all costs in order to slow down the avancing German troups. Miller and his men have no choice but join the group in defending the bridge if the want fulfill their mission. Eventually during the decesive battle Miller dies on the bridge in Ryan's arms in the same moment that American troups arrive as a reenforcement.