Some time after the wedding of Lex Luthor and Ardora of Lexor, Luthor returned to the planet Earth, leaving Ardora pregnant with his child. When he eventually returned, he was elated to discover that Ardora had bore him a son. Lex Jr. died when a battlesuit malfunction caused the ultimate destruction of the planet Lexor.
- This version of Lex Luthor, Jr., including all history and corresponding appearances, was erased from existence following the collapse of the original Multiverse in the 1985–86 Crisis on Infinite Earths limited series. Even though versions of the character may have since appeared, this information does not apply to those versions.
- 1 Appearances of Lex Luthor, Jr. (Earth-One)
- 1 Images featuring Lex Luthor, Jr. (Earth-One)
- Quotations by or about Lex Luthor, Jr. (Earth-One)
- Character Gallery: Lex Luthor, Jr. (Earth-One)