Which CSI episode served as the backdoor pilot for CSI: Miami?

“Cross Jurisdictions” served as the backdoor pilot for CSI: Miami. The CSI: Crime Scene Investigation episode brought Las Vegas investigators Catherine Willows and Warrick Brown to Miami, where they worked with Horatio Caine and the characters who would headline the spin-off.

The episode aired as CSI season 2, episode 22, and as the 45th episode overall, on May 9, 2002. Its story begins with a murder and kidnapping case connected to Miami, allowing the episode to introduce the new show's setting, investigative style, and principal characters within an established CSI story.

A backdoor pilot is an episode of an existing series designed to launch a potential spin-off. “Cross Jurisdictions” is sometimes confused with “Kitty,” which served as the backdoor pilot for CSI: Cyber, or “MIA/NYC NonStop,” which introduced CSI: NY. “Cross Jurisdictions” specifically belongs to the CSI-to-CSI: Miami transition.