Three months after joining Jor-El, Clark crash lands back on Earth with no memory of who he is but he is found by Chloe's cousin Lois Lane who is investigating her cousin's death. Lex finds an artifact with links to Krypton in Egypt.

The mystery surrounding Chloe's death deepens as Clark and Lois investigate, discovering that Lex Luthor and Lois' abrasive and militarist father, U.S. Army General Sam Lane, are somehow involved. Meanwhile, Lana returns to Smallv...

Without the approval of his father, Clark kicks off senior year by trying out for the Smallville High Football Team, who are now coached by Lana's new boyfriend, Jason Teague. Former acne-ridden nerd Abigail Fine returns from the ...

The Smallville High cheerleaders are using a kryptonite mixed love potion to seriously change the behavior of their victims.

Clark meets a young man with a power of speed that exceeds his own, but the boy lacks responsibility for his actions. Also, Lex finds a manuscript that appears to be some sort of Kryptonian map.

Lionel Luthor, using one of the Kryptonian stones, attempts to swap bodies with Lex but inadvertently transfers bodies with Clark, leading to him learning a few secrets, including that of Clark's powers.

A mysterious bookie with powers of manipulation has a strange, even dangerous, effect on Clark and his friends. Meanwhile, Lex causes friction by using his influence on Jason and Lana's relationship.

In 1604, in southern France, Lana Lang's distant ancestor Countess Margaret Isabel Thoreau and two other evil witches are condemned to be burned at the stake by Magistrate Wilkins, but Isabel manages to spit her blood on a symbol ...

Lex gets wrapped up in a sex/murder scandal. Clark gets Lionel's help to get Lex out of trouble. Lana meets Jason's mother, whom she has seen before in a dream, which was set in the 1600s.

After an explosion at a LuthorCorp lab, Smallville's citizens "relive" their worst nightmares.

Alicia Baker returns, and with the help of Red Kryptonite, elopes in Las Vegas with Clark. Lana offers a sexual relationship to Jason in an attempt to win him back. Lionel comes back to Lex with a peace offering.

When Lana is attacked in her apartment and Jason in his car by an invisible being, everyone believes that Alicia Baker was responsible, except Clark. However after a series of circumstances, Clark begins to doubt Alicia's innocenc...

As Chloe begins to see Clark in a new light after witnessing his abilities, a star football player from Metropolis University arrives in Smallville to convince Clark to take up their offer of a scholarship. Lex offers Jason a new ...

When Lois hits a dog with her car, she takes him back to the Kent farm where Clark discovers he has super strength that matches his own. Two brothers are desperate to get their hands on the dog, but for what purpose?

The Kryoptonian metallic disc is returned to Clark following the death of Virgil Swann. Placing the disc in the cave reveals a message from the spirit of Jor-El instructing Clark to find the three Kryptonian knowledge crystals and...

The Kents are surprised when Lois's sister Lucy arrives at the farm looking for a place to stay but Clark discovers she is on the run from Swiss loan sharks with whom Lex has past dealings. Jason is alarmed to find the stone is mi...

A LuthorCorp experiment involving black kryptonite ends in failure, causing Lex to be split into two, his good half and his evil half. Clark must find a way to reverse the process before the evil Lex achieves world domination.

It's almost graduation, and that means it's time for the prom. After a car accident, a meteor-infected student in-the-run for Prom Queen starts body-swapping. Meanwhile, a dead body is found on Lex's mansion grounds.

Kevin Grady commits thefts and uses his superpower to delete the incident from witnesses' minds. When he does so with Clark who stopped him after robbing The Talon, much more memory gets wiped, so Chloe must take super-boy home to...

In the middle of the night on the road, a young pregnant woman is going into labor while the father of her child drives, when she suddenly glows and implodes, while the guy stops the car and runs for his life. Lana and Clark are d...

On the last day of Smallville High before graduation, the emotionally disturbed and frustrated photographer of the Torch, Brendan Nash, feels rejected by the Universities and decides to abduct some schoolmates to stay with him for...

When Lana (possessed by Isobel) kills Genevieve Teague by stabbing her with one of the Kryptonian Knowledge Crystals after she attempts to steal it, it triggers a cosmic event that not only severs Lana's link to the spirit Isobel ...