Fear Doirche, meaning literally the Dark Man in Irish. A malevolent fairy, the chief agent of mortal abduction, usually in the service of a fairy queen. Very few that are taken by him to fairy land, or the sidhe (Celtic Mythology), ever return to tell the tale. In Irish mythology he belongs with the Tuatha Dé Danann and is prominent in such tales in the Fenian Cycle as The Birth of Oisín.
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Fear Doirche Wikipedia(Text) CC BY-SA