Lois Lane officially comes into Smallville at the start of season 4 , making her first appearance in the episode “Crusade” (Season 4, Episode 1).

She arrives in town to investigate the apparent death of her cousin Chloe Sullivan , which pulls her into Smallville’s drama and leads to her temporarily enrolling at Smallville High and sticking around as a main character.

So if you’re watching in order: you won’t see Lois at all in seasons 1–3, and she joins the show right when season 4 kicks off.

TL;DR:

  • Lois first appears: Season 4, Episode 1 – “Crusade”.
  • Reason she comes: Investigating Chloe’s supposed death.

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