Marg Helgenberger is set to return to the hit show "CSI: Crime Scene Investigation" for its 300th episode despite already ending her role in season 12 due to season and character changes - her return is considered as the writers huge milestone for the popular show, considering that she has established a large name not only for her character but as well as for the entire series.

Helgenberger or "Catherine Willows" for the hit show is to reprise her role once again by solving a seemingly impossible 10-year-old cold case for a season 14 episode, CBS claims that this is its way of satiating the actress's fans.

"We were just really excited to have Marg come back because, obviously, she's such an important part of the history of 'CSI' ... And she was super excited. It was kismet," said CSI executive producer Don McGill.

The popular TV personality has received several Emmy and Golden Globe nominations for her endearing and quite realistic portrayal of a female forensic scientist.

The star tweeted that she was quite excited to be back for CSI's 300th episode. It can be noted that in her previous press statement in January 2012 on whether she is willing to take part in a special episode for the show, she answered "Absolutely," adding that one of the reasons why she is glad to have worked for the popular TV series is that producers have given her an affirmation that she is free to come back to the show whenever she wants to, or whenever she's available for an appearance.

McGill also shared that the season finale will take all of its viewers back to the very beginning with major flashbacks of the case that actually began 14 years ago and with special participation from Helgenberger and other former CSI actors including George Eads, Eric Szmanda, Marc Vann, and Jorja Fox. The episode will probe into the evolution of the characters as well as that of the case that is deemed very emotional, yet fun-filled and meaningful all the same.

CSI season 14 is to return on September 25, at 10 p.m. ET. The show's 300th episode that will feature Marg Helgenberger and CBS's "Intelligence" actor, John Holloway, will be aired on Oct. 23.