The first episode tells the story of the meteor shower that hit Smallville and changed life in the Kansas town forever. Clark Kent meets Lex Luthor for the first time and encounters the first in a long line of humans mutated by the strange green meteor rocks that accompanied him on his journey to Earth.
Clark must deal with Greg, a nerdish bug collector with a crush on Lana who gains the ability of various insects and uses them to lash out at anyone who opposes him.
An abusive and hot-tempered football coach gains the ability to control and project fire.
Clark begins experiencing "vision problems" as his x-ray vision begins manifesting. Meanwhile a mysterious shapeshifter is going about town using his or her abilities to steal and get others in trouble.
A jock named Sean gains the ability to absorb heat from everything and everyone around him, and begins preying on people to gain the heat he needs to survive.
An old man uses green meteor rock to reverse the aging process, then gain vengeance on the children of the jury that put him away decades earlier. Meanwhile, another woman at the same old folks' home has prophetic abilities and she sees the futures of both Clark and Lex.
A weight-obsessed teen dieting on kryptonite-infected vegetables gains her fondest dream...but must feed on the fat of others to maintain her enhanced appearance.
An experiment at the Luthor fertilizer plant makes an old friend of the Kents literally shake and jitter, and he seeks vengeance against the Luthors, who hide the secret of his transformation behind "Level Three" at the local plant.
Clark visits Metropolis in this episode, and does a secret good deed - a police detective named Phelan witnesses his action and begins blackmailing Clark to help protect him from an IA investigation.
An invisible stalker is pursuing Lex and one of the household staff may, or may not, be responsible.
A salesman has a kryptonite-based ability to force anyone he touches to obey his commands.
On a class trip, Clark and a fellow student named Eric are struck by lightning, and because Eric was holding a piece of kryptonite, Clark's powers are transferred into him.
Whitney falls in with some former jocks who have kryptonite tattoos that give them the power to walk through walls. Meanwhile, Chloe is seriously injured and Lex has his own plans.
A man from Lex's past stalks him in conjunction with a mysterious passing at Club Zero that Lex may have been responsible for. Meanwhile Chloe looks into Clark's past as an adopted child.
A flower that comes from a reopened "Level Three" of the fertilizer plant brings strange reactions from several people, including Jonathan, Lana, and Pete.
A young runaway, Ryan, has the power to read minds and flees his abusive stepparents. The Kents take him in and Clark soon discovers the boy's powers and that he's immune to them. But Ryan's stepparents have plans to use the boy's powers for financial gain against...Lex.
Tyler gains the power to destroy organic matter with a touch, and resolves to put the dying out of their misery...and Whitney's father is his next target. Meanwhile Lionel and Lex spar over Lex's rising success in Smallville.
Clark gets into a class election and one of his opponents is a krypto-mutant who can control bees. Meanwhile a reporter from Metropolis visits to do a story on Lex.
After being injured in a hit and run accident, a student loses the use of his hands but gains the ability of telekinesis.
After an explosion Lana finds herself getting visions of a serial hugger...and his next target is Chloe. Meanwhile Lex and Roger look further into the meteor shower and determine that something besides meteors hit Smallville that day.
Lex is hit with a surprise after his father closes the local Smallville plant to force him back to Metropolis, blaming the plant's failure on his management. Meanwhile Clark prepares for his date with Chloe, reporter Roger Nixon gets wind of Clark's alien origins after setting up an explosion, and Whitney joins the Marine Corps.