Inhabiting a "pocket universe" created by the villainous Time Trapper, this young Luthor never loses his hair and admires the exploits of Superboy (a teenage Clark Kent) on his world. After Superboy's death, Luthor explores the hero's lab and accidentally frees three pocket universe Kryptonian villains from the Phantom Zone. To help the situation, Luthor creates an artificial life form out of a "pseudo-plasm matrix", based on the physical traits of Lana Lang. The life form is called Supergirl. After the Kryptonian villains kill Luthor and all other life forms on Earth, the pocket universe Supergirl makes a new home on the mainstream DC Comics Earth, where she becomes a hero.