Entertainment

‘Willows’ back to ‘CSI’ for 300th ep.

Marg Helgenberger will return to “CSI” for the show’s milestone 300th episode.

Helgenberger, 54, who played investigator Catherine Willows for 12 seasons, left “CSI” in January 2012. She’s set to star in a new CBS drama, “Intelligence.”

In her return, Willows will help the “CSI” team solve a decades-old cold case.

Not returning for the 300th episode: former “CSI” star William Petersen, who played “CSI” chief Gil Grissom.

Petersen, one of the show’s executive producers, left as a series regular in 2009, with the stipulation he might appear from time to time.

He’s returned only once since then, for an episode that aired in 2011.

“CSI” kicks off its 14th season Sept. 14.

The 300th episode of the still-popular CBS series will air Oct. 23.