Marg Helgenberger's Final ‘CSI’ Episode: Watch a Preview Here (Video)

Prepare for tonight's soon-to-be emotional departure with an advance glimpse

Marg Helgenberger says goodbye to "CSI" Wednesday night after 12 years on the show, in a move that will surely have Catherine Willows fans reaching for the Kleenex.

In this sneak preview of Helgenberger's swan song, Willows slips into a jiggle joint with D.B. Russell (played by Ted Danson) and makes a number of revelations, including the secret connection between stripping and sleuthing.

Helgenberger's final "CSI" episode, entitled "Willows in the Wind," airs Wednesday night at 10 on CBS. In the meantime, prepare yourself for her departure — and perhaps learn a little something in the process — by watching the video morsel below.