James Marsters

James Marsters will return for the final season of Smallville.

Supergirl Laura Vandervoort returns to Smallville

The 47-year-old Buffy alum, who sat on the Caprica panel on Friday in San Diego, announced he was returning as Brainiac in the 200th episode of Smallville

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Brainiac, the artificial intelligence construct created by the Kryptonians, was last seen near the end of Season 7 when he took over Kara's body, then faced off against Clark after nearly killing Chloe (Allison Mack).

Marsters can next be seen in the Hawaii Five-0 pilot, where he plays Alex O'Loughlin's nemesis.

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Reps for the CW series did not immediately respond to TVGuide.com's request for comment.