The movie opens in November 1941 with a British submarine-launched commando raid on the shores of Libya. The target of the raid is General Erwin Rommel of the German Afrika Korps, who is enjoying considerable success against British troops in North Africa. The daring raid produces plenty of casualties but misses Rommel. Rommel is gaining legendary status with his British enemies.
A captured British Lieutenant Colonel, Desmond Young, soon has a chance encounter with the celebrated Rommel in the midst of a desert artillery barrage. Rommel treats Young with respect and chivalry, inspiring the British officer after the war to investigate the life and mysterious death of the great general.
Rommel's story is told in retrospect, beginning with the defeat of German forces at El Alamein in late 1942. Rommel, by now a Field Marshal, had been away from the front on medical leave, but he is forced to return in an attempt to stem the British tide. Rommel fights gallantly but becomes increasingly disenchanted with Hitler's interference and maniacal insistence on victory or death.
Shortly before the total defeat of German forces in North Africa in the spring of 1943, Rommel is again invalided back to Germany. In the hospital, Rommel is visited by his wife Lucie (Jessica Tandy), his son Manfred, and Dr. Karl Strolin (Cedric Hardwicke), the Lord Mayor of Stuttgart and an early conspirator against Hitler. Strolin's presence arouses the suspicion of the SS and Gestapo. Rommel confides to Strolin that Hitler has accused him of cowardice and hinted at having him shot, and that Hitler had callously abandoned his beloved Afrika Korps. He further confides that Hitler no longer believes victory is possible, and that he only fights on because the Allies would never make peace with him. That can only mean that Germany and her people will be forced to fight to the death. Strolin provides Rommel with a dire warning about Hitler's unstable and vindictive nature.
Rommel returns to active duty in November 1943, overseeing the defensive preparations for the expected Allied invasion in the West. Rommel works tirelessly to improve the woefully weak German fortifications. Reporting back to Field Marshal von Rundstedt (Leo G. Carroll), Rommel learns that Hitler himself is directing most aspects of the war. Von Rundstedt further warns Rommel that he will be under constant suspicion from Berlin.
While Rommel is home on leave in February 1944, Dr. Strolin makes another attempt to enlist him in the growing conspiracy against Hitler. Rommel is offended and horrified at the thought of a military coup, and the discussion becomes heated. Strolin leaves without a commitment.
Rommel soon returns to France and continues his defensive preparations. When D-Day arrives and the Allies gradually manage to expand their beachheads, Rommel frets over misallocated troops while von Rundstedt ridicules Hitler and his arbitrary decisions that tie their hands. Seeing an opening, Rommel tries to enlist von Rundstedt in the conspiracy to remove Hitler. But Rundstedt begs off, saying that while he agrees with them, he is too old to revolt. Rommel requests a final meeting with Hitler before firmly committing to his overthrow. The meeting is a disaster; Hitler blasts Rommel as a defeatist and promises miracle weapons that will soon turn the tide in Germany's favor.
Rommel now resolves to join the other conspirators, remove Hitler, and sue for an honorable peace. But then, his staff car is caught on an open road by Allied fighter planes and badly strafed. Rommel is seriously injured. While he is recuperating in a French hospital, the failed July 20, 1944 assassination attempt against Hitler takes place.
Three months after the assassination attempt, General Keitel phones Rommel, who is still convalescing at home. Keitel supposedly wants to inquire about Rommel's health and readiness for another command. When Rommel explains that it will be another few weeks before he is ready, Keitel offers to send someone down from Berlin to discuss a future command with him. The next day, General Wilhelm Burgdorf and another officer arrive at Rommel's home. Ominously, a truckload of armed soldiers waits on the main road.
Rommel and the two officers retire to a private room to talk. Rommel is suddenly presented with a list of treason charges against him, stemming from the bomb plot. Rommel initially chooses to stand trial and address the charges, but it soon becomes apparent that he will not get the chance. Burgdorf makes it plain that Rommel's family will be in jeopardy should he not accept the only real option left to him- a poison capsule. In return, his family will be taken care of and Rommel will be publicly hailed as a national hero who succumbed to his war wounds. This deception will serve to prevent embarrassment for Adolf Hitler.
Rommel bids a sad farewell to Lucie, his son Manfred, and his loyal aide Aldinger (Richard Boone). He then climbs into a staff car with the officers for a short and final ride. The film ends with a heartfelt tribute from Winston Churchill, who honored Rommel as a worthy adversary and decent man who came to hate Naziism.