Throughout the CSI show, inspiring CBS to expand its universe. Its success resulted in the network ordering the first spinoff, CSI: Miami, in 2002, and the second one, CSI: NY, in 2004. CSI was a cultural phenomenon that forever changed the course of TV (in numerous respects).

As of the writing of this article, the CSI franchise has no current shows airing, as the latest, CSI: Vegas, ended with its season 3 finale in May 2024.

Every series in the franchise revolved around a CSI team, consisting of forensic scientists, detectives, and medical examiners who work together to solve murders. However, as one could tell by their titles, each show took place in a different city. The CSI franchise started in Las Vegas before heading to Miami, and then New York City. Given the series' varying locations, crossovers were difficult, but the producers made it work for one game-changing event that transpired for three episodes, one from each CSI show.

CSI's "Trilogy" Crossover Is When The Crime Procedural Franchise Peaked

"Trilogy" Was The First Time All 3 Shows Crossed Over

Although "Trilogy" wasn't the first time some characters from the CSI universe interacted, it was the first time all three TV shows crossed over with one another. CSI: Miami's backdoor pilot aired during CSI season 4, bringing the two series together. A couple of years later, CSI: Miami hosted CSI: NY's backdoor pilot. CSI: Miami and CSI: NY debuted another crossover shortly afterward, as well. However, everything was different in "Trilogy" as it was the first (and only) crossover between all three shows, and nothing has been the same in the franchise ever since.

CSI Show

Season #, Episode # For "Trilogy"

Episode Title

Director

Writer

Release Date

CSI: Miami

Season 8, Episode 7

"Bone Voyage"

Sam Hill

Barry O'Brien

November 9, 2009

CSI: NY

Season 6, Episode 7

"Hammer Down"

Scott Lautanen

Peter M. Lenkov and Pam Veasey

November 11, 2009

CSI: Crime Scene Investigation

Season 10, Episode 7

"The Lost Girls"

Alec Smight

David Weddle and Bradley Thompson

November 12, 2009

"Trilogy" began on CSI: Miami before continuing on CSI: NY and ending on CSI: Crime Scene Investigation. Laurence Fishburne's Ray Langston was at the center of the crossover's story. Ray searched for a lost girl who was dragged into a human trafficking ring, and the case led him to Miami and New York before heading back to Las Vegas. It was beyond exciting for the audience to see characters from three of their favorite shows interact with one another in "Trilogy." Given the franchise's success and popularity at the time, no other crossover event could ever come close to it.

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"Trilogy" Confirmed CSI As The Best Shared Universe On TV At The Time

CSI Had No Competition After The Crossover

Since the airing of "Trilogy" in 2009, big crossover events between TV series and their spinoffs have only gotten more common. Beforehand, something as big as a three-show crossover was unheard of. Years later, though, the Arrowverse and the One Chicago universe often followed/follow CSI's model. However, nothing could beat the original, and "Trilogy" only confirmed why the CSI franchise is and always will be one of TV's best shared universes.

CSI Franchise Poster
Created by
Anthony E. Zuiker, Carol Mendelsohn, Ann Donahue, Jason Tracey
Cast
William Petersen, Marg Helgenberger, Gary Dourdan, Paul Guilfoyle, Jorja Fox, Louise Lombard, Patricia Arquette, James Van Der Beek
TV Show(s)
CSI: Vegas
First TV Show
CSI: Crime Scene Investigation
Character(s)
Gil Grissom, Catherine Willows, D.B. Russell, Sara Sidle, Calleigh Duquesne, Mac Taylor, Stella Bonasera, Avery Ryan, Elijah Mundo, Josh Folsom
Video Game(s)
CSI: Crime Scene Investigation, CSI: Dark Motives, CSI: 3 Dimensions of Murder, CSI: Hard Evidence, CSI: Miami, CSI: NY, CSI: Deadly Intent, CSI: Crime City, CSI: Fatal Conspiracy

CSI: Crime Scene Investigation is a multi-media franchise that began with the self-titled original series developed by Anthony E. Zuiker. The series follows various detectives as part of the CSI teams as they work behind the scenes (and in the field) to uncover the truths behind unsolved murders. The series has also enjoyed an extensive collection of simulation-style video games over the years as companions to ongoing television shows.