Catherine Willows (Marg Helgenberger, left) uses her flashlight with Sara Sidle (Jorja Fox) as they look into the trunk of a car, on the milestone 300th episode of "CSI." / CBS
(CBS NEWS) Marg Helgenberger returns as Catherine Willows in tonight's (Oct. 23) landmark 300th episode of CBS' "CSI: Crime Scene Investigation."
She will help solve a cold case that has haunted the team for 14 years. Jason Priestley guest stars as casino mogul Jack Witten, who "once threw the most lavish parties in Las Vegas, until a scandal tainted his reputation."
To mark the 300th occasion, the episode will have the number "300" hidden 14 times throughout the show. Viewers are encouraged to spot them down and check to see how they did following the show by visiting CBS.com for a full list of the audio and visual cues.
"CSI" premiered on Oct. 6, 2000, and currently stars Ted Danson, Elisabeth Shue, George Eads and Jorja Fox.
Danson recently told "CBS This Morning" that the secret to a hit show like "CSI" all comes down to the writing. "Writing attracts the good actors, then you get the great directors. But it starts in the writing."
"CSI" airs Wednesday nights at 10 p.m. ET on CBS.
Lauren Moraski, CBS News