Arianna Carlin (Emma Samms) Luthor's ex-wife arrives in Metropolis seeking revenge for his death and her targets are Lois and Superman, whom she thinks responsible for it. With the help of Dr. Heller (Earl Boen), a plastic surgeon who worked for Lex and she later kills, she creates a duplicate of Lois. Dr Carlin used her books to get the public to hate Superman and turn against him and make Lex Luthor like a hero. The duplicate does things that Lois would never do, like accusing Superman for killing Lex or throwing a tear gas in the newsroom of Daily Planet, to make everyone believe that Lois got crazy. At the same time, Arianna gets hired by Perry on the Daily Planet as a therapist and pushes everyone to believe even more that Lois is not herself and she needs help. Clark decides to help Lois investigate the truth even though he is not sure if he has to believe her when she says that she is fine. Eventually, they discover the true identity of Arianna as Lex's ex-wife and they reveal the truth but not before Arianna captures Lois and attempts to kill Superman using kryptonite making it look like Lois did it. Lois manages to help Superman and he makes sure that Arianna and the duplicate gets arrested. Dr. Gretchen Kelly (Denise Crosby), who is taking care of Lex's body that was stolen at the end of season one after his death, tells him that Arianna failed but he will always have her.