A name for Sauron's Ruling Ring after it came into the possession of Gollum during the Third Age. Lost by Isildur as he attempted to escape from the Disaster of the Gladden Fields, the Ring lay beneath the waters of Anduin for nearly two and a half thousand years. It was rediscovered by two friends, Déagol and Sméagol, and Sméagol was so drawn by the allure of the Precious, as he later called it, that he murdered his companion and kept it for himself.

Eventually driven out by his people, Sméagol - or Gollum - crept into the darkness beneath the Misty Mountains and kept his Ring in the depths. The Ring's power consumed him, but also extended his life unnaturally, and he guarded his Precious in the caverns beneath the Mountains for nearly five hundred years. As the Third Age drew into its closing decades, a traveller came to Gollum's lair; a lost adventurer named Bilbo Baggins who stumbled across the Ring by accident and took it, quite unaware of its significance at that time. Thus the Ring left Gollum and the Misty Mountains, finding its way through many adventures back to Bilbo's home in the Shire. There it remained quietly until the last years of the Third Age, and the setting out of the Fellowship of the Ring.

Meanwhile Gollum had become desperate to recover his Precious, and set out from the Mountains in pursuit of the creature that he considered to be its thief. Setting out to follow Bilbo's trail, he was drawn to Mordor, where the name of Baggins was discovered from him. Through further travails he found himself eventually in Moria, where he came upon the Company of the Ring, and he followed the Ring-bearer to the Cracks of Doom. There he finally recovered it, but he fell into the Fire of Mount Doom, bringing about his own end, and that of the Ring that he had guarded in the dark for five centuries.