Warning: The Following contains spoilers for season 5 of "Game of Thrones" and the "A Song of Ice and Fire" novels.

"Game of Thrones" fans have busied themselves ever since the season five finale with thinking up every conceivable theory that would allow Jon Snow to return after the character was dealt a seemingly fatal blow. But loyal book readers of George R.R. Martin's "A Song of Ice and Fire" novels have been diligently unearthing any and all clues to another theory for years now: Jon's true parentage.

Jon has always been presented as Ned Stark's bastard son, but both the show and the books have dropped little clues hinting that that is not actually the case. The most popular theory is R + L = J. For the uninitiated, that means "Rhaegar Targaryen" + "Lyanna Stark" = "Jon Snow."

Rhaegar is the son of the Mad King, while Lyanna was Ned's sister. It is believed that Rhaegar kidnapped Lyanna, sparking Robert's Rebellion, though some in Westeros believe the two were secretly in love. Most Westerosi aficionados tend to believe the latter.

What is known is that Ned, Howland Reed and several other companions traveled to the Tower of Joy near the end of Robert's Rebellion because Lyanna was being guarded there by several members of the Kingsguard. What followed was a bloody confrontation between the two groups that left only Ned and Howland alive. The two entered the tower to find Lyanna dying in "a bed of blood." But before she died, she made Ned promise her something. What that promise is, no one knows.

But fans may finally get some clarity on the issue in season six of "Game of Thrones." According to the Spanish site Movistar, production for season six will make a stop at Castillo de Safra in Guadalajara, Spain. The castle, with its tall, singular tower, resembles the description of The Tower of Joy.

In addition, the list of new characters the show is adding next season included one entry that any "A Song of Ice and Fire" fan worth their salt could have identified as Ser Arthur Dayne, captain of the Kingsguard who was present at the Tower.

So will "Game of Thrones" finally be showing this famous scene? All signs appear to be pointing to it.