Déagol is a fictional character in J. R. R. Tolkien's legendarium. His story is related in The Fellowship of the Ring, the first of three volumes comprising Tolkien's most famous novel, The Lord of the Rings, in the chapter "The Shadow of the Past".
In 2463 of the Third Age, Déagol became the third bearer of the One Ring, after Sauron and Isildur. He found the Ring—which had been lost for thousands of years—while fishing with Sméagol in the Gladden river.
Instantly ensnared by its beauty and seductive power, Sméagol demanded the Ring as his "birthday-present". When Déagol refused to give it up, Sméagol strangled him and hid his body, which was never found; nevertheless, the murderer (nicknamed Gollum after the swallowing noises he made) was eventually driven from his home and into the Misty Mountains.
The name "Déagol" is from Old English dēagol (more commonly spelt dīegol), meaning "secretive". In Tolkien's Red Book of Westmarch, the name "Déagol" is used as a translation of the "original" name in the author-invented language of Westron, "Nahald", which has the same meaning.
In Peter Jackson's 2001–2003 live-action adaptations of The Lord of the Rings, Déagol is played by New Zealand actor Thomas Robins. His scenes with Andy Serkis (Sméagol/Gollum) were originally planned to be in The Lord of the Rings: The Two Towers, but were moved to The Lord of the Rings: The Return of the King.
- Tolkien, J. R. R. (1980), Christopher Tolkien, ed., Unfinished Tales, Boston: Houghton Mifflin, Part Three, IV. "The Hunt for the Ring", p 353, note 9, ISBN 0-395-29917-9. In a letter quoted by Christopher Tolkien, Tolkien refers to Déagol and Sméagol as Stoors.
- Tolkien, J. R. R. (1954), The Fellowship of the Ring, The Lord of the Rings, Boston: Houghton Mifflin (published 1987), "The Shadow of the Past", ISBN 0-395-08254-4 They are popularly thought to be cousins, but Tolkien only calls them "friends" in The Lord of the Rings. In a later letter (The Letters of J. R. R. Tolkien, #214) he writes that they were "evidently relatives".
- Tyler, J.E.A. (1977). The New Tolkien Companion. ISBN 0380469049.