In the Autumn of 1939, Hank Heywood reconciles with his girlfriend, Gloria Giles. Giles wants to hear no more talk of the war in Europe. A war Giles hopes America never enters. Heywood, however, believes America has a responsibility to intervene. From an upstairs window, Giles' father, Gilbert, watches the two lovers. Professor Giles reflects on recent events. Foiling German saboteurs had resulted in Heywood suffering near fatal injuries. Using an experimental bio-restorative process, Giles was able to save Heywood's life, while also transforming him into a powerful cyborg.
Shortly after Heywood's recovery, the mysterious, militarist adventurer, Steel, the Indestructible Man, began breaking up spy rings. Giles fears that Heywood may, in fact, be Steel, the Indestructible Man. In Washington D.C, famed German industrialist, Baron Toten, meets with Doctor Moag. Toten, with his manservant, Bruno, has come for a demonstration of Moag's latest invention, the Transmuter. Moag places a rock into the Transmuter, exposing it to the "Omega" Field. Using vocal commands, Moag orders the rock to sprout limbs, and move towards him.
Toten is astonished, quickly deciding to steal the Transmuter for the Third Reich. Bruno attacks Moag. In the course of the struggle, Moag stumbles back into the Transmuter. Moag is transformed into an enormously powerful creature, composed of molten rock. Moag also finds he has internalized the ability to wield the "Omega" Field. Moag, calling himself the Mineral Master, animates the marble floor, driving Toten, and Bruno, from the premises. Heywood, as Steel, the Indestructible Man, leaps from an airplane.
Steel, the Indestructible Man, has arranged a demonstration of his abilities, for Jack Kulhammer, a congressman who sits on the House Armed Services Committee. Also in attendance are Kulhammer's daughter, Kathy, high ranking military personnel, and Kathy's boyfriend, Edward Runyon, a newspaper magnate. Steel, the Indestructible Man, is hoping to convince the War Department of his usefulness, as a secret weapon against the Third Reich. Unfortunately, spectacular as Steel's demonstration is, Congressman Kulhammer disbelieves the veracity of it.
Steel, the Indestructible Man, is written off as a charlatan. An explosion, detonated in a hanger housing bombers, draws Steel, the Indestructible Man into conflict with the Mineral Master. Steel, the Indestructible Man, is astonished by the Mineral Master's incredible powers. After a brief battle, the Mineral Master departs on a flying piece of sod. Steel, the Indestructible Man, tries to continue the fight. The Mineral Master knocks Steel, the Indestructible Man, from the earthen platform. Steel, the Indestructible Man, falls, landing on, and crushing, Kulhammer's limousine.
The Mineral Master commandeers the airwaves, at a well-known radio station.The Mineral Master demands that America stay out of the war in Europe, threatening to slay those men in power who support America entering the war. Heywood deserts his post to confront the Mineral Master, as Steel, the Indestructible Man. Steel, the Indestructible Man, storms the radio station, with the police hot on his heels. Steel, the Indestructible Man, attacks the Mineral Master. Unwittingly his rash attack carries Steel, the Indestructible Man, and the Mineral Master, out the window.
The Mineral Master stops his fall by catching himself with a concrete hand, drawn from the very walls of the station. Steel, the Indestructible Man, digs his hands into the wall, to slow, and eventually, stop his fall. The Mineral Master transforms a street lamp into an arrow-firing bow. Steel, the Indestructible Man, catches the arrow, and hurls it at the Mineral Master. The Mineral Master transforms the arrow into a flock of metal birds. Steel, the Indestructible Man, taunts the Mineral Master into blindly attacking.
The Mineral Master tackles Steel, the Indestructible Man, sending them both plummeting towards the street. Contact with the ground serves to make the Mineral Master even more powerful. An epic brawl ensues. Ultimately, Steel, the Indestructible Man, is triumphant. Steel, the Indestructible Man, holds the unconscious form of the Mineral Master off the ground, for twelve hours, until the power drains out of the Mineral Master. The Mineral Master, powerless, is turned over to the authorities. Steel, the Indestructible Man, is left wrestling with his desire to join the war effort against his love for Gloria Giles.
- This issue contains the Hostess Superhero Ad, Superman in "The Big Fall".