 Schmidt and Dr. Arnim Zola harness the energies of the Tesseract , intending to use the power to fuel Zola 's inventions , mounting an offensive that will change the world . Schmidt discovers Erskine 's location and dispatches assassin Heinz Kruger to kill him . Erskine subjects Rogers to the super @-@ soldier treatment , injecting him with a special serum and dosing him with " vita @-@ rays " . After Rogers emerges from the experiment taller and more muscular , an undercover Kruger kills Erskine and flees . Rogers pursues and captures Kruger , but the assassin avoids interrogation by committing suicide with a cyanide capsule . With Erskine dead and his super @-@ soldier formula lost , U.S. Senator Brandt has Rogers tour the nation in a colorful costume as " Captain America " to promote war bonds while scientists study him and attempt to rediscover the formula . In 1943 , while on tour in Italy performing for active servicemen , Rogers learns that Barnes 's unit was MIA in a battle against Schmidt 's forces . Refusing to believe that Barnes is dead , Rogers has Carter and engineer Howard Stark fly him behind enemy lines to mount a solo rescue attempt . Rogers infiltrates the fortress of Schmidt 's Nazi division Hydra , freeing Barnes and the other prisoners . Rogers confronts Schmidt , who removes a mask to reveal a red , skull @-@ like visage that earned him the sobriquet " the Red Skull " . Schmidt escapes and Rogers returns to base with the freed soldiers . 
