Clark is trapped in the Phantom Zone, a barren desert full of criminals that were sent there by Jor-El. His only hope of escaping lies with a mysterious woman. Back on Earth, Zod plans to use Kryptonian technology to create New Krypton. Martha and Lois land near the Fortress of Solitude where Jor-El instructs Martha to kill Zod.

Clark develops a cold for the first time which leads to the discovery of a new ability. Lex hires a private investigator to find out who it is that's following him. Meanwhile, Lois writes her first article on the weather.

Clark, Chloe and Jimmy investigate a strange vine that is killing people in the woods. Meanwhile, Lex throws a costume ball to benefit the victims of Dark Thursday.

After writing an article about the 'Green Arrow Bandit', Lois is kidnapped. Lex lets Lana in on his latest project, studying the mysterious black box.

Lex and Oliver meet up at the Excelsior Academy 10 year reunion. When two of his friends die in suspicious circumstances soon after, Oliver suspects Lex is involved.

Clark is reunited with Raya but there's little time to catch up as Baern, a phantom from the Phantom Zone, makes his way to Smallville intent on killing Clark.

The Green Arrow is shot whilst trying to save a couple from a carjacking. Clark finds Oliver is alive and well the next day but his behaviour is somewhat erratic so Clark attempts to get to the bottom of Green Arrow's miraculous recovery. The rivalry between Oliver and Lex comes to a head whilst Lana receives some shocking news.

Lex is imprisoned in another plane of existence by a man who can shift through alternate frequencies. Meanwhile, a Zoner is sucking the bones out of people in Seattle and Clark must investigate and prevent any more grisly deaths occurring.

Clark discovers illegal immigrants are being exploited at the neighbouring farm and seeks help from Martha to allow a boy and his mother to stay in the country.

When the Daily Planet's gossip columnist, Linda Lake, publishes a story on Clark, Lana and Lex using details from a private conversation, Lana accuses Chloe of betraying her. Lois begins to suspect Oliver might be the man behind Green Arrow.

Oliver introduces Clark to some familiar faces, who are now working alongside Green Arrow. When one member of the team is captured during a mission, Clark must help the others mount a rescue effort. Lois looks forward to a trip to Monte Carlo but Oliver has some disappointing news for her.

Clark wakes up in a mental hospital where the physician in charge, Dr. Hudson, informs him that the past five years were not real and only a figment of his imagination. Clark must come to terms with life as a normal human being as Dr. Hudson tries to persuade him to accept his treatment to cure his paranoid schizophrenia.

Lois tries on lipstick made with red kryptonite and becomes infatuated with the first man she sees... Clark. The two share a kiss which causes Clark to lose all of his inhibitions and he decides to gatecrash Lana and Lex's engagement party.

Lana receives a photo of herself, taken inside the mansion and decides to hide from her stalker in a surprising location. Jimmy thinks Chloe still sees Clark as more than a friend and breaks up with her.

Clark and Chloe discover that Lex is using a young man's ability to identify meteor freaks to help him further his experiments. When Lana finds out, she tries to persuade him to stay silent, fearing he'll expose Clark as one of the infected.

On Lex and Lana's wedding day, Dr. Langston threatens to tell Lana the truth about her pregnancy but Lex will do anything to silence him. Clark is willing to tell Lana his secret in order to stop Lana marrying Lex.

Clark and Chloe locate another Zoner in a fight club which prompts Clark to seek a way in, knowing he'll probably have to expose himself. Lois catches wind of the fight club and desperate for a good story, she manages to get in but is put up against a fighter she wasn't expecting.

Lex brings Chloe's mother, Moira, out of her catatonic state and uses her to control other meteor freaks. Lana makes a shocking discovery about her pregnancy.

When Lex is trapped deep inside underground tunnels by the wife of a former test subject, Clark sets off to find him but is rendered powerless by the kryptonite-laden walls. The only way the two of them will make it out alive is if they put their differences aside and help each other.

Chloe and Jimmy are shocked to find Lana has been shot in the elevator at the Daily Planet. Jimmy is knocked unconscious whilst studying photos of the scene and dreams of Metropolis in the 1940s.

A crooked senator threatens to expose Lex's secret labs where he's developing a super soldier so he sends Wes Keenan to kill him. When Lois witnesses the attack, she becomes Wes' next target.

John returns to defeat the last phantom but it proves to be a tough task. Clark confronts Lionel after he discovers Lana was blackmailed into marrying Lex. Lana leaves Lex and plans to get away from Smallville whilst Lois heads to Reeves Dam in search of Lex's secret laboratory.