Eads played forensic investigator Nick Stokes ever since the series' pilot in 2000, but exited at the conclusion of CSI's 15th season earlier this year.
While the actor had never officially signed on to the special, creator Anthony E. Zuiker had already written Nick into the script. Now that Eads has decided not to participate in the project, the script will have to undergo a minor revamp, though it's unclear whether or not Stokes' absence will be directly addressed.
Eads is not the only cast member who isn't returning for the long-running procedural's swan song. According to Entertainment Weekly, Elisabeth Shue won't be reprising the role of Julie Finlay, which she played since 2012.
However, there will be plenty of familiar faces in the goodbye special. William Petersen (Gil Grissom) and Marg Helgenberger (Catherine Willows) will return, along with Ted Danson (D.B. Russell), Jorja Fox (Sara Sidle), Jon Wellner (Henry Andrews), David Berman (David Phillips), Paul Guilfoyle (Jim Brass), Wallace Langham (David Hodges), Elisabeth Harnois (Morgan Brody), Robert David Hall (Dr. Al Robbins), Eric Szmanda (Greg Sanders), and Melinda Clarke (Lady Heather).
The CSI finale special airs Sunday, Sept. 17 on CBS.
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