It's 1943 and a mine is producing magnesium for the war effort. A group of Nazis are nearby trying to sabotage the ore production and some of their men have jobs in the mine. The Range Busters arrive with Alibi taking a job in the mine and then being immediately fired. Claiming to want revenge against the mine owner gets him accepted among the saboteurs and his eavesdropping enables Crash and Denny to move just as the saboteurs plan to strike.