The One Ring, also called the Ruling Ring and Isildur's Bane, is a central plot element in J. R. R. Tolkien's The Lord of the Rings (1954–55). It first appeared in the earlier story The Hobbit (1937) as a magic ring that grants the wearer invisibility. Tolkien changed it into a malevolent Ring of Power and re-wrote parts of The Hobbit to fit in...