In 1943, Capt. Harold 'Cal' Calvert [Wendell Corey] is sent to Smoky Hill, Kansas, to learn the ropes of piloting the groundbreaking Boeing B-29 Superfortress. He studies hard under his sharp-eyed instructor, Maj. Tom West [Forrest Tucker], a seasoned officer whose reputation among the squadron is mixed—some suspect he earned his stripes by claiming engine trouble on a raid over the Ploesti oil fields. When a crewman taunts West’s absence of fear in front of the nurse he’s involved with, Lt. Helen Landers [Vera Ralston], Cal finds himself defending his cousin and ally in front of the woman both pilots admire.
As training progresses, the group discovers just how remarkable the pressurized, high-flying B-29 can be: it can soar higher, climb faster, and reach farther than previous bombers. During a tense test flight, Cal pushes beyond the flight plan, triggering a dangerous decompression. A crewman is sucked briefly from the aircraft but manages to deploy a parachute and survive. West is furious at Cal for risking the test program, which the Air Force brass are watching closely because the new plane represents the future of long-range aerial bombardment.
Maj. Gen. Wolfe [Walter Brennan] eventually declares the pilots and their aircraft ready for combat and sends them toward bases in China to begin assaults on Japan. The initial missions are harrowing, yet the B-29s prove their effectiveness in real-world operations. The unit is later reassigned to Guam, where Tom is finally reunited with Helen, who has joined the forces there as well. Cal finds himself flying nearly nonstop on high-altitude missions, while the strategic mindset of Gen. Curtis E. LeMay [William Witney] pushes the squadron toward a controversial shift: low-altitude raids designed to inflict heavier, more immediate damage on enemy targets.
As Helen’s affection for Cal deepens, their unit participates in a mass raid on Tokyo. The mission takes a brutal turn when their B-29 is struck by anti-aircraft fire. Wounded, Cal clings to life while Tom stays at the controls in a bid to bring the crippled aircraft home. He makes a harrowing decision, plunging back into the fiery wreckage to rescue a trapped crewman, only to be killed when the plane explodes. The loss marks a painful turning point as the war edges toward its end.
In the weeks that follow, as dramatic events unfold with the Allies deploying even more devastating weapons, the war comes to a close. Amid the chaos and relief of victory, Cal and Helen find a shared future: a quiet, enduring bond forged in the skies and in the heat of battle. The film draws a measured portrait of courage, sacrifice, and perseverance under pressure, illustrating how duty and affection intertwine when the fate of nations hangs in the balance.
