<P> During the story of Smallville, Lionel evolves from being a nemesis of Clark Kent (Tom Welling) who develops multiple schemes to uncover Clark's secrets, to becoming an ally who eventually dies to protect Clark's secret from his own son . Lionel has a strained relationship with Lex and regularly tries to test him . He attempts to develop a romantic relationship with Martha Kent following the death of Jonathan Kent, helping her advance toward the United States Senate . </P> <P> Lionel's development from a main antagonist to an ally was difficult for the writers, who felt the character's arc failed to achieve the status they wanted . Although they continued with the story arc, Lionel returned to using deception to protect Clark rather than exploit him . He is characterized as a sinister character who tried hard to further his own ambitions . Lionel's relationship with his son has been likened to that of Harry Osborn and Norman Osborn from Spider - Man comics . </P> <P> In 1989, Lionel visits Smallville to buy the Ross Creamed Corn company immediately before a meteor shower occurs . Twelve years later during season one, Lionel exiles his son Lex Luthor (Michael Rosenbaum) to Smallville to run LuthorCorp's local fertilizer plant as a test . When Lex makes a profit for the first time in years, Lionel closes the plant and blames Lex's poor managerial skills . Lionel later confronts his son at the Luthor mansion when Lex tries to orchestrate an employee buyout to save the fertilizer plant . When strong winds force debris to smash through the mansion, Lionel is pinned under a fallen support beam and Lex hesitates to save his father . In Season two, Lex saves Lionel but loses his sight because of Lex's judgment to rush into surgery . Season two's first half shows Lionel as blind . Lex and Lucas Luthor (Paul Wasilewski)--Lionel's illegitimate son--devise a plan to uncover Lionel's deception; it is revealed that Lionel was blind but that his eyes healed and he intentionally neglected to tell anyone so he could watch how they acted around him . Season two's second half shows Lionel is aware of the Kawatche caves and tries to unlock the mysterious symbols there, to the dismay of Clark Kent (Tom Welling). </P> <P> Season three revealed that Lionel conspired with Morgan Edge (Rutger Hauer) to murder Lionel's parents and use the insurance money to fund the start of LuthorCorp . Lionel has Lex committed to a mental institution, when his son discovers what Lionel did . When Chloe Sullivan (Allison Mack) discovers the truth, that evidence is used to assist Lex have Lionel arrested for his parents' murder . Season three also revealed why Lionel is angry with Lex; he blames his son for the death of his youngest son Julian Luthor, although Lex took the blame to protect the true killer, his mentally unwell mother Lillian (Alisen Down). Lionel also learns that he has a terminal liver disease, which he divulges to Lex while awaiting arraignment . </P>

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