Arlene was born in Smallville, a little rural town in Kansas. Nothing is known about her family of origin, but as a young woman she met Jules Luthor, a salesman she fell in love with. The two got married, and they moved to the town's suburbs, in Jules' family farm; soon after they had two children, Lex and Lena. Since Jules was often away for work, it was up to Arlene to raise her children, and when he grew up, Lex helped with the farm; as the woman soon realized, however, he was far too smart to be a farm boy: he was actually a natural-born genius, who felt limited in the suburbs. In order to grant their son more stimuli, the Luthors moved to Smallville, where Lex became a fan of the local hero, Superboy, and even started helping him. Soon enough, an unfortunate series of events led Lex to consumed by envy and paranoia, and he started a lethal competition with Superboy: while trying to kill the hero over and over again, Lex also endangered the entire Smallville more than once, using his intellect to build futuristic but deadly machines. Arlene was surely aching to see her son act like this, but she had to take care of Lena as well: along with Jules, she decided to protect their youngest daughter, so they disowned their first born, and left Smallville forever. In order not to be found, the Luthors changed their name into Thorul (a simple anagram of Luthor), and they told Lena that her beloved older brother had died in a tragic car accident. Quite ironically, both Arlene and her husband were eventually killed in a true tragic car accident, and their daughter was raised in an orphanage.
- This version of Lex Luthor's mother, 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.
- 7 Appearances of Arlene Luthor (Earth-One)
- 1 Images featuring Arlene Luthor (Earth-One)
- Quotations by or about Arlene Luthor (Earth-One)
- Character Gallery: Arlene Luthor (Earth-One)