A map overlays the opening scenes, accompanied by a voiceover that traces the United States military presence on Wake Island up to November 1941. Maj. Geoffrey Caton (played by Brian Donlevy) lands at Wake Island aboard a Pan American Clipper to assume command, and immediately clashes with the civilian contractor Shad McClosky (played by Albert Dekker) over a sprawling trench and shelter-building project. The island’s defense hinges on grit and improvisation, and Caton’s arrival sets the stage for a clash between military discipline and civilian enterprise, all while the threat of war looms larger with each passing day.
As Caton investigates, he identifies two young Privates, Aloysius K. "Smacksie" Randall and Joe Doyle, portrayed by William Bendix and Robert Preston respectively, who are already under strain in a system that prizes order over convenience. He orders them to dig a substantial trench by hand, a task meant to harden the defenses but also a microcosm of the friction between the military and the civilian workforce. McClosky’s drive to finish his large-scale trenches and living quarters on time intensifies these tensions, as the civilian crew presses forward under pressure while the military upper ranks want to maintain efficiency and readiness. The clash underscores a fragile balance on an island that is about to be tested by a far larger force.
The narrative pushes forward with the dawn of December 7, 1941. Randall’s enlistment is coming to an end, and news from Pearl Harbor jolts Wake Island into a state of high alert. Randall, unsure of what to do next, retreats with civilians to a bomb shelter as enemy aircraft close in. In the sky above, a squadron of Japanese bombers presses an overwhelming assault—four Americans push back against twenty-four attackers, managing to shoot down several planes even as the island absorbs heavy bombardment. The battle marks a brutal turning point, with human courage tested against the brutality of the air and sea onslaught.
Back on the ground, Caton makes a hard decision: he informs Lt. Bruce Cameron (played by Macdonald Carey) that his wife, Sally Cameron (uncredited, portrayed by Barbara Britton), was killed at Pearl Harbor. The personal cost of war weighs heavily on the command structure, even as the defense rigs up makeshift responses and Cameron formulates a bold plan to strike back. When a Japanese heavy cruiser comes within range, Caton orders a clever plan by Cameron to strip a fighter plane down to a bare 15 gallons of fuel while carrying a double payload of bombs, a move that tests resources, nerve, and ingenuity in equal measure. Cameron is wounded in the ensuing aerial action, but he manages to complete the mission and makes a perilous, controlled landing, before succumbing to his injuries.
With dwindling large-caliber ammunition, Caton widens the defense by dispersing his forces and equipping them with smaller weapons. Japanese air raids persist, exacting heavy damage and casualties, and the island’s last lines of defense are strained to the limit. The island endures a particularly brutal moment when the final American pilot, Captain Bill Patrick (played by Damian O'Flynn), is killed while bailing out of a damaged craft. As the air and sea dominion of the attack intensifies, the Marines and civilians fight to hold the line against overwhelming odds.
Facing a renewed Japanese demand for surrender, Caton refuses to yield and issues a stark reply, “Come and get us,” signaling that his posts should act independently and endure as long as possible. When communications fail, Caton orders the last man to depart with a written message, a moment of solitary resolve in a losing battle. McClosky returns, seeking a weapon, and together they relocate to an abandoned machine-gun position where Caton takes the gun and holds their ground. The Japanese force breaches the defenses, and one by one the principal characters fall in action. The film closes on a somber note, with a voiceover declaring the grim truth of war:
> This is not the end.
