‘CSI’ Series Finale First Look: Marg Helgenberger, Paul Guilfoyle Are Back in Action (Photos)

In the first official images from “CSI: Immortality,” we see fan favorite characters Det. Jim Brass and Catherine Willows back in action.

Marg Helgenberger, who plays Willows, departed the series after the 12th season, while Paul Guilfoyle, who plays Brass, left the show after the 14th. Both will return, along with Gil Grissom (William Petersen), for the two-hour finale event.

Plot details for the finale are scarce, but we know that former members of the Las Vegas Crime Lab return to action after a catastrophic event paralyzes Las Vegas. Sara Sidle (Jorja Fox) is also forced to make a decision regarding her career.

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Lady Heather (Melinda Clarke) will also return for the finale, but former cast members George Eads and Gary Dourdan, who played Nick Stokes and Warrick Brown respectively, will not. Ted Danson, who plays lab leader D.B. Russell, will move to “CSI: Cyber.”

“CSI: Immortality” airs on Sept. 27 on CBS.

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Take a look at the stills from the event below.