The Skeleton Key (also called the Skeleton's Key) is a Daedric artifact created by the Daedric Prince Nocturnal. In appearance it doesn't always take the form of a key, and sometimes manifests as a lockpick instead. In its key form, it can be used to unlock any lock. As a lockpick, it is nigh unbreakable and can get past even the toughest locks. The two limitations placed on the Key by wizards who sought to protect their storehouses were that the Key could only be used once a day and it would never be the property of one thief for too long, eventually disappearing.
The artifact functions as a tool for "unlocking" all things, including portals, hidden potential, and other unknown possibilities. Its ultimate function, however, is to unlock and hold open the Ebonmere, a portal to Nocturnal's realm, Evergloam, located in the Twilight Sepulcher of Skyrim. The Nightingales are tasked with guarding the Sepulcher and retrieving the Key should it be stolen. Unfortunately, the Prince is said to allow the Skeleton Key to be stolen or lost periodically, whether by purpose or apathy.
The first supposed wielder of the Key was the thief Arrovan. After disappearing, the Key always chose inaccessible places to hide, and for the benefit of historians Arrovan made a list of the various resting places.
In the mid-Second Era, the key was in the possession of Sotha Sil, who kept it in his Clockwork City. After the key was used by Nocturnal in a plot to take over the Clockwork City, Sotha Sil gave the Skeleton Key to the Telvanni wizard Divayth Fyr for safekeeping.
The Skeleton Key was later uncovered during the Imperial Simulacrum by the Eternal Champion in either Valenwood or Summerset Isles (reports vary) while following rumors of the Key having appeared in one of the known dungeons. In the events leading up to the Warp in the West, an unknown agent of the Blades was tasked by Nocturnal to kill a mage in his stronghold. The agent was then gifted the Key by a worshipper of the Prince.
The Key later came into the possession of Gentleman Jim Stacey, leader of the Thieves Guild in Vvardenfell. The Key was passed on to the Nerevarine in 3E 427, although how Stacey came to lose it is unclear: some say it was in return for killing Sjoring Hard-Heart, the Master of the Vivec City Fighters Guild, while others say the Nerevarine took it by force.
Circa 3E 433, an artifact known as the Eye of Nocturnal was stolen from Nocturnal's shrine in Cyrodiil's Blackwood region. Nocturnal tasked the Champion of Cyrodiil with recovering it. The thieves, an Argonian couple in Leyawiin, hid it in a flooded cave in Topal Bay. The Champion returned it to Nocturnal and was rewarded with the Skeleton Key.
Some time before 4E 201, the Key was stolen from the Twilight Sepulcher by Mercer Frey, a corrupt Nightingale. Its long-term loss resulted in a decline of the Skyrim branch of the Thieves Guild due to bad luck without Nocturnal's influence. The guild's influence declined until their only presence was in the Ratways beneath Riften. Mercer used the Key to bring himself luck, but he was eventually confronted by the Nightingales beneath the Great Statue of Irkngthand. Mercer was killed, and the Last Dragonborn brought the Key back to the Sepulcher, reopening the Ebonmere.
- Events of ESO: Clockwork City
- Events of Arena
- Events of Daggerfall
- Events of Morrowind
- Events of Oblivion
- Events of Skyrim