Originally aired May 1, 2008
Written by Turi Meyer & Al Septien
Directed by Tom Welling
Clark learns that Brainiac has traveled back through time to kill baby Kal-El and thus eliminate Clark from the timeline, but he thinks everything will be better for everyone if he hadn't made it to Earth. Jor-El then shows Clark what would happen if he hadn't made the trip to Earth.
Tropes present in the episode:
- Adam and Eve Plot: In the Alternate Universe, Brainiac mentions that he plans to have Zod (in Lex's body) and Kara re-populate the devastated Earth with new Kryptonians so Krypton will be reborn.Alt!Brainiac: With the humans gone, I would use Kara to release [Zod] through her Fortress.Clark: She'll never go along with it.Alt!Brainiac: It didn't look like she had much fight left in her. But she'll heal. She's healthy. So is Lex Luthor, the vessel. Together, [Kara and Zod] will re-populate the planet, and Krypton will rise again.
- Alternate Universe: Jor-El sends Clark to one to show him why his presence on Earth is important.
- Apocalypse How: Class 5 in the Alternate Universe.
- Betrayal Insurance: President Lex carries a handgun loaded with Kryptonite bullets in case Kara ever turns on him.
- Cataclysm Climax: The episode's turning point is set on Krypton as it nears annihilation.
- Disappointed in You: Jor-El tells Clark such when he reveals everything he's seen was All Just a Dream.Jor-El: You disappoint me, my son. You cannot question your destiny on this planet.
- Driven to Suicide: Clark prepares to let Brainiac kill his infant self on Krypton so he'll be eliminated from existence because he believes everyone and everything will be better off without him.
- Event Title: The episode refers to the end of the alternate Earth and to Krypton's impending destruction in the climax.
- Evil Chancellor: In the AU, President Lex's Chief of Staff Milton Fine AKA Brainiac.
- Infant Immortality: Averted. Brainiac time-travels to Krypton just before it explodes so he can kill baby Kal-El. Fortunately, he's stopped by Kara and then Clark.
- It's All My Fault: Clark blames himself for everything bad that's happened on the show thus far—the meteor showers, meteor freaks, Brainiac, etc.Clark: Ever since I arrived, all I brought is death and suffering, meteor freaks, phantoms, Brainiac.Chloe: Clark, you've done so much good. You can't blame yourself for all the bad in the world.Clark: It's not blame, Chloe. I'm taking responsibility for all the lives that I've ruined, including Lana's.
- It's a Wonderful Plot: Just as Clark contemplates what is basically suicide, Jor-El shows him what life would be like for everyone if he hadn't made it to Earth. It isn't exactly pretty.
- Light Is Not Good: President Lex wears a white suit, but he's planning to devastate Earth so he can rule over the survivors in a new world.
- The Man Behind the Man: Brainiac to President Lex in the alternate reality in his guise as Milton Fine, Lex's Chief of Staff.
- Make Wrong What Once Went Right: Brainiac goes back in time to erase Clark from existence.
- Man in White: President Lex wears a pristine white suit.
- Mythology Gag:
- AU!Jimmy wears a bowtie.
- AU!Lana is married to a French businessman named "Pierre Rousseau," which sounds similar to Pete Ross, whom she married in the past comics continuity.
- Clark wears a suit and glasses while posing as a reporter.
- Never the Selves Shall Meet: Defied. Clark time-travels to Krypton moments before its explosion and he puts his infant self into his ship, preserving the timeline.
- Pillar of Light: Clark is enveloped in one once again as Jor-El speaks to him.
- Red Right Hand: In the AU, President Lex wears a black leather glove.
- Stable Time Loop: Clark travels back through time to moments before Krypton explodes and manages to place his infant self into his spaceship while Kara deals with Brainiac.
- Time Travel: The Fortress has this ability, according to Kara's message in Swann's diary.
- Time-Travel Episode: Clark travels back through time to save his infant self from Brainiac.
- What Happened to the Mouse?: We never learn what happened to Jor-El and Lara once Brainiac came to kill their infant son.
- Would Hurt a Child: Brainiac goes back in time to just before Krypton explodes so he can kill infant Kal-El, ensuring that Clark won't exist in the future.
- You Can't Fight Fate: Jor-El says this to Clark before bringing him back to the actual reality.Jor-El: You cannot change the course of history, Kal-El.