It's almost time to bid adieu to CSI: Crime Scene Investigation - the series that not only changed the face of television, but also so permeated society that it gave prosecutors headaches the world over.

'CSI: Las Vegas' Finale: Nick Stokes Won't Even Be Mentioned? EP Talks George Eads Absence

CSI: Las Vegas will air its two-hour swan song this Saturday (Sept. 27), and the procedural juggernaut is ready to wrap up loose ends and thank their devoted fans for 15-years of deadly fun.

"We've told a lot of stories in 15 years. We're trying to complete some of the dangling pieces," returning alum William Petersen (Grissom) said in a new featurette. "We hope that we're able to do this series proud by saying goodbye in the right way."

'CSI: Las Vegas' Finale: First PHOTOS Revealed, See Grissom & Willows In 'Immortality'

If the "right way" is to bring back the series' most beloved characters, than CSI is certainly fulfilling Petersen's wishes with "Immortality Part 1 & 2". Grissom, Captain Jim Brass (Paul Guifoyle), and Catherine Willows (Marg Helgenberger) will all return when a crisis grips Sin City.

"There's nothing unexciting about the finale," Eric Szmanda (Greg) teased. "From the first scene to the last scene, there are acknowledgments and tributes to highlights of the show over 15 years."

Are you ready for CSI's final case? Check out what the rest of the cast has to say in the video below!

Tags: CSI: Crime Scene Investigation television CBS