"CSI" is coming to an end and original cast members are reuniting to make the two-hour-long finale the most special episode of the well-loved crime TV series.

E! News sid that the end of "CSI" as something similar to "the end of an era." After 15 seasons and over 300 episodes, several major players of the show are making a comeback in the special two-hour series finale due on September 27.

In an interview with TV Line, "Under the Dome" star Marg Helgenberger expressed her excitement at the upcoming reunion with the CSI original cast.

"I'm excited... that all of us are going to be back. I think it's going to be a really fun time," she explained during the San Diego Comic-Con.

Reuniting in the episode are Eric Szmanda, Jorja Fox, Paul Guilfoyle, William Petersen, and Helgenberger who shared behind-the-scenes photos over her official Twitter account.

"#OGCSI Great fun today with this gang!" she captioned a group photo where she is seen with Fox, who plays Sara Sidle, Szmanda as Greg Sanders, Guilfoyle as Jim Brass, and Petersen.

Petersen also posed with Helgenberger, a.k.a Catherine Willows, in another photo showing a reunited "Grillows."

To excite CSI fans further, TVLine compiled a slideshow of more behind-the-scene snaps of the cast and crew during the filming of the final episode that Entertainment Weekly reported began on July 29 in Los Angeles.

A July report from Entertainment Weekly also revealed more stars to be featured in CSI's farewell episode including David Berman who plays David Phillips, Wallace Langham as David Hodges, Robert David Hall who portrayed Dr. Al Robbins, Elisabeth Harnois as Morgan Brody, and Melinda Clarke as Lady Heather.

The report also said that while most of the original cast will return, Elisabeth Shue, who portrayed Julie Finlay, and George Eads as Nick Stokes would not be making a comeback during the finale.

TV Line previously revealed that Eads chose not to participate in the show, leaving CSI creator and writer Anthony E. Zuiker to give the finale script a little tweak to remove his character from it.

Meanwhile, an Entertainment Weekly report revealed that the show's producers were unsure how to handle the absence of Shue's Julie Finlay, who had been in the series since 2012, from the "epic" final episode of CSI.

Producing the CSI swan song temporarily entitled "Immortality" are Carol Mendelsohn, Jerry Bruckheimer, Jonathan Littman, Ann Donahue, and Petersen.