'Grimm': Alexis Denisof Makes His Royal Debut (Exclusive Video)

The "Much Ado About Nothing" star hits up the NBC drama this Friday as the revenge-seeking Prince Viktor, desperate for justice for Eric's untimely death.

NBC is doubling up on Grimm with a two-hour fall finale.

Much Ado About Nothing star Alexis Denisof makes his debut as Prince Viktor in the first episode -- titled "Cold Blooded" -- of Friday's back-to-back offering.

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The Hollywood Reporter exclusively premieres a tense scene between Viktor, Captain Renard's (Sasha Roiz) cousin who is hell-bent on gaining power for himself at any cost, and Adalind (Claire Coffee). Viktor recounts his close relationship with his deceased cousin Eric and his devastation over Eric's "violent" and "obscene" death.

"I'll do everything in my power to bring to justice the men responsible for this act...or women," he says, tasking Adalind to serve as his family's counsel after revealing that he has intimate knowledge of her relationship with Eric. Viktor then asks about his "half-cousin" Sean and Nick (David Giuntoli), leading him to give Adalind a difficult task: write down a list of names of those in Portland who may have had a hand in Eric's murder.

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Good luck with that Adalind.

Watch the scene below.

Grimm wraps up the first half of the season with a two-hour fall finale Friday at 9 p.m. on NBC.

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