In the far reaches of space, a fiery rocket ship is on a collision course with Earth … specifically Metropolis! Just in the nick of time, Superman, Supergirl, Superboy and Krypto save the ship, and its pilot, Captain Corben, from crashing into the Metropolis Seaport. But his ship went through a Kryptonite asteroid field and now Corben has Kryptonite poisoning and he’s not happy! Taking a cue from Lex Luthor, Captain Corben straps on a metal suit, calls himself Metallo and sets out for revenge on Superman! Resonating with Kryptonian energy, will Metallo defeat Superman? Hint: not if Steel has anything to say about it!