The Gray Fox is the guildmaster of the Thieves Guild. He gets his name from his sneakiness in thievery and from the gray mask, the Gray Cowl of Nocturnal, that he wears. The first Gray Fox stole the cowl from the Daedric Prince Nocturnal herself. The title of Gray Fox is passed from leader to successor by giving the Gray Cowl of Nocturnal to the successor. Since the successor then becomes the Gray Fox, many think that he has been alive for over 300 years.
In the book Purloined Shadows, a young female thief is enlisted to help a master thief. During a ritual performed by witches, Nocturnal is summoned, and she removes her cowl during the ritual. The young thief is hiding there, waiting for the master's signal to steal the cowl. Suddenly, the master's voice cries out, warning Nocturnal of the young thief's presence. Nocturnal turns and begins to strangle the young thief. The young thief, before she dies, notices that the cowl has disappeared. It is presumed that the master thief then dons the cowl and becomes the Gray Fox, activating the curse of the cowl in the process.
It is unknown whether the book is true or not, but it tells possibly the only full story of how the Gray Fox came to be in possession of the cowl. The names of both thieves are never revealed in the book; however, at the end of the Thieves' Guild quest line, the current Gray Fox names Emer Dareloth as the true thief of the cowl.
It is revealed later that the current Gray Fox is Corvus Umbranox, the Count of Anvil. The curse of the Cowl caused his real identity to be erased from history, forcing him to continue his life known only as "The Stranger". Though he had been missing for ten years, with the help of the Hero, he lifts this curse from himself at the end of The Ultimate Heist and returns to his wife, the Countess of Anvil Millona Umbranox. He passes down the Cowl to the Hero to succeed him as Gray Fox and the Grandmaster of the Thieves Guild, thus they become the new Gray Fox.
Methredhel or Amusei tells the Hero that the Gray Fox wants an audience with them at Helvius Cecia's House in Bruma. There, the Gray Fox tasks the Hero with stealing the Savilla's Stone from the Temple of the Ancestor Moths. Returning to the Gray Fox with Savilla's Stone and the note "Instructions: the Gray Cowl" allows the Hero to ask him about the Cowl's nature.
Amusei tells the Hero that the Gray Fox requested an audience at Malintus Ancrus' House in Chorrol. The legendary thief tasks them with stealing the Arrow of Extrication from Fathis Aren's Tower through a hidden passage in Castle Bravil.
Amusei tells the Hero is requested at a meeting at Garendhel's House in Cheydinhal. After a brief conversation, the Gray Fox tasks the Hero with retrieving the Boots of Springheel Jak. After speaking with Jak's descendant, Jakben, Earl of Imbel, the Hero must then battle five vampires in order to recover the Boots. However, there were no Boots, instead the Hero finds a diary, revealing that Jakben was in fact the legendary Springheel Jak and that he sent the Hero to a trap. The Hero must then defeat Jak in order to recover his boots and deliver them to the Gray Fox.
The Gray Fox tasks the Hero with stealing an Elder Scroll. After recovering the Scroll, the Gray Fox uses it to reveal the identity of the true thief, Emer Dareloth, and return to his normal life.
There are several references to the Gray Fox in Skyrim:
- During the Thieves Guild questline, the Bust of the Gray Fox can be found in Mercer Frey's house. The bust is a larceny target for Delvin Mallory, and upon turning it in, will appear on the guildmaster's desk. Delvin will also state that Mercer Frey admires the Gray Fox.
- When in the Pelagius Wing of the Blue Palace, the Dragonborn is teleported into the Pelagius' mind. With in-game subtitles turned on, Sheogorath mentions several things pertaining to the life of the Hero of Kvatch, including "a Fox," with a capitalized F.
- Upon completing the Thieves Guild questline, Ravyn Imyan will occasionally praise the Dragonborn as they pass him, but comment that they are no Gray Fox.
- The Gray Fox was voiced by Wes Johnson.
- If the Hero attempts to pickpocket the Gray Fox they will find in his inventory the same outfit that the Stranger wore in Taking Care of Lex. This is likely an Easter egg as the Stranger is the Gray Fox not wearing the Gray Cowl. This is hinted at when confronting him with the note in Turning a Blind Eye. He'll say they've met once before, but because of the Gray Cowl the Hero's mind interprets them as two different people.