On Christmas Eve, Lex travels to a dangerous neighborhood in Granville, Kansas, dealing dirty means to cut Jonathan Kent of the race to the senate. He is shot twice in cold-blood when a couple of junkies steal his car, and Lex has a near-death vision of having a possible middle class lifestyle with a pregnant Lana as his wife and their son Alexander. In his near death experience, Lex is a simple man beloved by the people of Smallville and best friend of Jonathan and Clark. Meanwhile in the real world, he is submitted to a life-threatening surgery ordered by Lionel to avoid becoming crippled. Also, Chloe asks Clark to deliver many Christmas gifts to poor children, and Clark meets a sad and disappointed Santa Claus contemplating suicide. In the end, Lex concludes that love is cursed, based on the fate of Julian, Lillian and Lana, and power and money are the most important values in his life... which leads to him finally starting down the path of the dark side beginning when he secretly orders the execution of the junkie couple who attempted to kill him.

While running for campaign to the senate, Jonathan hires Lois as his advisor. Meanwhile, his opponent Lex is visited by a group of fans lead by the fanatic Samantha Drake, and the deranged woman threatens the safety of Jonathan by attempting to assassinate him at a political rally by using Lois to carry out the deed. Meanwhile, Lana discusses with Clark their sex life on why he no longer wants to make love to her, and Clark exposes his innermost fears to Chloe that Lana will discover his secret superpowers if he continues his romance with Lana. Elsewhere, Lionel takes and eliminates the dossier Griff has prepared to Lex to discredit Jonathan, and offers his financial support to Martha.

Clark decides that he is ready to start his training at the Fortress of Solitude to become 'Superman'. However, the spirit of Jor-El insists that he return to Metropolis to cut his ties with the people he knows before he begins. Lois reappears in the city with no recollection of vanishing to the future. Her investigation into a monorail crash brings her into contact with a new reporter named John Corben. John is opposed to the "Red and Blue Blur", and has a secret power and identity himself. Meanwhile, Chloe's friendship with Clark deteriorates when he refuses to use the Legion ring to go back in time to save Jimmy. Elsewhere, Oliver turns down a dark path in his quest to rid the world of evil. General Zod makes his entrance at the Luthor mansion before Tess.

Jor-El mysteriously arrives at the Kent farm to hide the Book of Rao, but meets Chloe instead. She tells him that his son, Kal-El is on Earth and lives at the farm. Convinced the Blur is Jor-El, Zod enlists Tess's help in finding him to force him to reveal the secret to his powers. Clark realizes Jor-El is alive and on Earth and races to find him before Zod does.

Tess kidnaps Lois to find out where Lois went after she disappeared for weeks. Lois's memory of the future depicts a Metropolis under Zod's rule and Clark powerless under the red sun, while Chloe forms a resistance group with Oliver. After learning of these future events, Clark makes an important decision about Zod.

Tess's latest intrusion, at Watchtower, and Chloe's excessive lockout mechanism, lock the pair up, likely to be killed while Checkmate breaks trough the last firewalls. Intrudening the Luthor mansion Oliver faces Zod, whose abusive side reemerges, now with superpowers. Clark must save his friends and hopes to do he same for the Kandorians, one of which carries unsuspecting Zod's unborn child, but the all-round secrecy exacts terrible prices.

Zod unleashes his army upon the world, forcing Chloe to call in reinforcements from old friends. Zod tells Lois he is The Blur and asks her to steal the Book of Rao from Clark. Torn between Clark and The Blur, Lois asks Clark to come clean with her about everything but he refuses. Chloe and Oliver attempt to reconnect Watchtower's satellite system in order to fight the Kandorians but to Chloe's horror, Oliver gets caught on site and disappears. Tess attempts to stop Zod but he leaves her clinging to life. Clark and Zod battle for control of Earth.