In Atom Man vs. Superman Kent/Superman is pitted against bald-pated Lex Luthor, who, disguised as Atom Man, threatens to devastate Metropolis with any number of devilish devices-the deadliest of which is a disintegration machine. Luthor stumbles onto Superman's Achilles' heel: Kryptonite. Once our hero has been exposed to this fatal ore, Metropolis becomes a wide-open town for criminals of all varieties. But Superman regains his full powers in time to stop Luthor from laying waste to Metropolis with his latest demon machine, a sonic vibrator.