20 Episodes · Premiered September 27, 2007 · Ended May 15, 2008
There are two Clark Kents. One is the young on destiny's path. The other is a Bizarro who shares Clark's DNA but not his values. Only one of them can survive. Superman mythology grows deeper and more powerful in an event-packed season that includes the arrival of Clark's cousin Kara/Supergirl. Keep a low profile and master your powers, Clark says. Kara has other ideas.
As the seventh season begins, Clark faces his most deadly enemy---his Bizarro doppelganger---after Lex's secret lab at Reeves dam is destroyed; Lex is saved from drowning by a mysterious female savior, but his past catches up with him.
Clark meets his cousin Kara, but decides that there is nothing for him in Smallville without Lana, so he heads to the Fortress of Solitude to begin training as a superhero. Once there, Jor-El tells him Kara's father is evil and she is dangerous, so Clark must return to Smallville.
Clark hopes Kara will keep a low profile, but three meteor-infected girls want to use her as part of their scheme after one of them sees Kara's special powers.
Lex employs Dr. Curtis Knox to cure the meteor-infected, and Chloe ends up a patient. Meanwhile, John Jones warns Clark that his cousin Kara should not be trusted.
Clark saves the life of a starlet on a film shoot in Smallville when a stunt car's brakes fail, but what happened was no accident. Meanwhile, Lionel finds himself the victim of a surprising captor.
In the process of trying to get the crystal back, Kara is captured and sedated with a kryptonite serum; Clark follows and tries to release her, but not before the serum has caused both to have a vision of Clark's mother.
Lana absorbs Clark's powers and uses them to go after Lex, first trying to expose his secrets in the Daily Planet, then moving on to a more personal level.
Clark makes a huge mistake when he releases Lara from the crystal, because Zor-El is also released. Elsewhere, the relationship between Lois and Grant heats up.
Clark comes home and tells Lana that Kara has vanished, and that they should work together to stop Lex; and a man named Adrian, infected with an alien substance, plants a bomb on Chloe, who then confesses to Jimmy that she is a meteor freak.
Clark is frozen in the Fortress and Bizarro takes over his life, starting with Lana, who shares information about Brainiac. Elsewhere, Grant reveals he is a clone of Julian, and Lex is shocked at his father's reaction to this revelation.
Chloe runs afoul of the Black Canary when she procures one of Lex's project files for Oliver. Lex suspects the Green Arrow and retaliates, while Lois discovers Oliver's secret.
Lois trails Lex to Detroit, where he has found Kara suffering from amnesia. A busboy obsessed with Kara shoots Lex so he can't take her away, and holds Kara and Lois captive. Chloe finds Lex and offers to heal him, but Clark will not let her.
Former Smallville resident Pete Ross, now a roadie for the band OneRepublic, accidentally chews kryptonite-laced gum and gets superpowers. Clark and Chloe try to warn him about the effects, but Lex finds out and uses Pete for his nefarious schemes.
Lionel kidnaps Clark and holds him in a kryptonite-lined cell at a Luthorcorp facility; Chloe and Lana confront Lionel, who blames Lex, and they then take Kara to the Fortress and plead with Jor-El to restore her memory so she can save Clark.
Kara teaches Clark how to fly to help him fight against Brainiac, but Brainiac seems to be a step ahead of them.
The secret of the Veritas society leads Lex into a collision course with Clark; and a death rocks Smallville.
Clark searches for Brainiac, who is the only one who can reverse Lana's condition; Chloe accidentally sets off alarms as she hacks into government computers while trying to find info to help Clark; the Department of Security threatens Jimmy with jail time unless he helps them arrest Chloe, while Lex offers to help clear Chloe, but only if Jimmy agrees to be in his debt.
Clark, through a series of messages sent by Kara from Krypton, discovers what Earth would be like had he never arrived: Jonathan is still alive; Lex is the president; the Luthors have raised Kara; Lana is happily married; and Chloe and Lois are ace reporters.
A cloaked stranger attacks Lex, leaving him with Kryptonian symbols carved on his chest. They were intended as a message for Clark, who investigates with Chloe and learns that one member from Veritas is still alive and hiding in a church.
In the seventh-season finale, Brainiac impersonates Kara, whom he has imprisoned in the Phantom Zone, and in her guise he takes Lex to the Fortress for a showdown with Clark. Meanwhile, Chloe is arrested by the Department of Domestic Security; and Lana awakens from her comatose state.
