Paul Krenner, an ex-major with delusions of grandeur, has forced scientist Peter Ulof to develop a radiation-based technique to turn men invisible, with which process he plans to create an invisible army to sell to the highest bidder. He busts safecracker Joey Faust out of prison and forces him to undergo the invisibility treatment so he can steal more radium to further the experimentation. Plans go awry when Faust discovers there is a side-effect to the invisibility treatments he didn't count on.