Manson will make his debut in the eighth episode of the season, which will air in mid-November.
"We've always been enormous fans of Marilyn Manson," creators/executive producers Eddy Kitsis and Adam Horowitz told Rolling Stone in a joint statement. "We wanted to cast someone with the vocal ability to make our skin crawl."
In the third season of the fantasy series, protagonist Emma, played by Jennifer Morrison, is on a mission to save her son, Henry, played by Jared Gilmore, from Neverland, but they encounter The Shadow, which so far has been a silent presence.
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