Helen Sloan/Courtesy of HBO

WARNING: This article contains spoilers about the latest episode of Game of Thrones.

The return of Jon Snow to Game of Thrones this season was shrouded in such intense secrecy that the words "Jon Snow" literally weren't allowed to be uttered on set.

As Entertainment Weekly reveals, "Jon Snow" did not appear in any of the Game of Thrones scripts, call sheets, prop or wardrobe materials. In order to avoid letting the big secret slip, everyone called Snow "LC," short for "Lord Commander."

“No one was allowed to say ‘Jon Snow’ on set, ever, everyone had to refer to me as ‘LC,’” says Kit Harington, who plays Snow on the show. 

Harington apologized to fans for keeping them in the dark on the fate of the character, who was killed last season and revived in the second episode of the current one. Although no one could say "Jon Snow" on set, they certainly could show his face in the first teasers for season 6!