It's a great day for angels and demons alike. Amazon's anticipated adaptation of Neil Gaiman and Terry Pratchett's novel Good Omens finally scored a premiere date as well as an incredible new guest star. All six episodes of the miniseries will be available to stream starting Friday, May 31, Gaiman announced Wednesday at the Television Critics Association winter press tour.

Gaiman, who took on the role of showrunner for the adaptation, was joined onstage for a panel teasing the series by executive producer and director Douglas Mackinnon and stars Michael Sheen and David Tennant, who star as angel Aziraphale and demon Crowley, respectively. While discussing the show's incredible cast - which also includes Jon Hamm, Michael McKean and Nick Offerman — Gaiman revealed that there was a new guest star to announce: Benedict Cumberbatch.

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The Sherlock star will appear in Good Omens' sixth and final episode as a 400-foot tall Satan. "As many of you know, Frances McDormand is playing God in this. And we suddenly realized we have Satan turning up in Episode 6 and we needed somebody who could give Frances McDormand a run for her money," Gaiman explained. "We needed a performance that would work, so we found a young British actor who needed a lot of direction ... It is the glorious, young Benedict Cumberbatch [who] is our Satan," he quipped. "He's marvelous."

Good Omens premieres Friday, May 31 on Amazon Prime.

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