When crafting Smallvilles version of Lex Luthor, series developers Al Gough and Miles Millar decided that he would not be a precursor to the more comedic role performed by Gene Hackman in the Superman film series; the pair wanted him to be likeable and vulnerable [REF].
Before Rosenbaum got the part, Martin Cummins auditioned for the role of Lex Luthor; Cummins would go on to play Dr. Garner, a neuro-scientist who experiments on Clark, in multiple episodes of Smallville spanning season two and three [REF].