The breeding ground was a monstrous walled castle completely covered over with a huge electrified net. Inside were the scum of the earth, gathered from the prisons of the world, transformed into invincible monster giants by the evil genius of Pere Teston. Now they were ready to ravage the world with their hideous menace – unless Doc Savage and his mighty crew could stop them.
#7 in the Doc Savage paperback series. Originally published in Doc Savage Magazine, 4/34