Exclusive: Battlestar's James Callis Digs Up CSI Dirt in Season 13 Finale

CSI Season 13 SpoilersThe Las Vegas CSI team this spring will not face off with a brutal killer or ruthless kidnapper, but a man armed with a poison pen.

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TVLine has learned that for the CBS crime drama’s Season 13 finale, airing May 15, Battlestar Galactica baddie James Callis will guest-star as a journalist who has the Las Vegas Police Department — including the CSI team — in his crosshairs, as he aims to expose the corruption and hypocrisy of those tasked with policing Sin City.

What’s more, Callis’ character is harboring a secret in his past.

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Since his run as BSG‘s Gaius Baltar, Callis has appeared on such series as Eureka, FlashForward and, just recently, The CW’s Arrow (as a thief dubbed The Dodger).

CSI resumes its season this Wednesday at 10/9c with guest stars Bree Williamson (Deception), T.J. Ramini (NCIS), Michaela McManus (Law & Order: SVU) and Adam Busch (Buffy the Vampire Slayer).