When a show is adapted from a best-selling set of novels, especially a series of books that have not yet been completed, there are bound to be more than a few long-running fan theories transferred between the series and its source material. Game of Thrones on HBO and the A Song of Ice and Fire novels by George R.R. Martin are no exception, spawning years of speculation about the characters and plot of the fictional world of Westeros.

Game of Thrones creators David Benioff and Daniel Weiss had to eventually create a conclusion independent of the source material, drawing on themes and foreshadowing from the books (as well as a conversation with Martin about how he intended to conclude the series, if he were to ever finish), to write episodes and seasons of television. This alchemy of adaptation allows for certain fan theories to last for years, or suddenly be canonized by a show that has surpassed the novels.

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Heading into the final season of Game of Thrones (premiering April 14 on HBO), here is a collection of some of the most popular fan theories, made up both of selections proven false and ones that turned out to be scarily accurate.

<p>Kit Harington on <em>Game of Thrones</em> </p>

Kit Harington on Game of Thrones

Jon Snow Wasn't Dead

In the last episode of Season 5, "Mother's Mercy," the Lord Commander of the Night's Watch suffered a mutiny at the hands of his Brothers. Jon Snow, lured out into the the courtyard of Castle Black by the false promise of the return of his Uncle Benjen, died when he was repeatedly stabbed. In the break between seasons, we were meant to believe Jon Snow bled out in the snow.

This was also where the most-recent A Song of Ice and Fire novel (A Dance With Dragons) left Jon, meaning book readers had a long time to speculate about the ultimate fate of one of the main characters of the series. Readers who also watched the show poured over Season 5 context clues to decipher hints at how Thrones was going to handle Jon's death, knowing HBO was about to forge ahead into unpublished plot.

Melisandre, The Red Woman, using her powers to resurrect Jon Snow was one of the leading theories fans clung to between seasons. Both in the show and in the books, the character Thoros of Myr is shown to have the power to resurrect Beric Dondarrion (the guy with the flaming sword). It was easy to speculate that the Lord of Light could grant this power to another one of their priests. There were other, less popular, theories — like one that involved Jon Snow warging into this direwolf Ghost — but almost no one in the Game of Thrones fan community believed Jon Snow was going to die for good stabbed to death in Castle Black.

<p>Kit Harington and Sean Bean on <em>Game of Thrones</em> </p>

Kit Harington and Sean Bean on Game of Thrones

R+L =J

As the television show built to endgame without the novels to use as source material, one of the lingering questions posed by the books suddenly returned to the franchise's plot with a renewed fervor: the parentage of Jon Snow. Since the show doesn't rely heavily on flashbacks outside of Bran's recent set of visions, the full backstory of how Ned Stark came to care for Jon was only discussed on-screen while Ned was still alive (outside of frequent references to Jon being a bastard).

The whole tale about Jon's secret Targaryen parentage was something that is heavily hinted at in the Martin novels, as readers get a larger sense of Ned Stark as the sort of man unlikely to have had an affair during wartime, and the story of Rhaegar Targaryen "kidnapping" Ned's sister Lyanna. The show references both of these narratives early on, leading book readers to speculate that Thrones was going to follow through with the implications from A Song of Ice and Fire.

What the fan base didn't see coming was that Bran would be the person to confirm Jon's true Targaryen lineage. In the books, there is still a living character who was at the Tower of Joy when Ned took a baby from his dying sister: Howland Reed, the father of Jojen and Meera Reed. The show chose to bypass bringing in that character to impart knowledge, instead splitting duties between Gilly's book-reading and Bran's magic plot-convenient visions.

Clegane Bowl

The showdown between the brothers Clegane is a long-running popular theory that has oscillated from seemingly impossible (when they were both presumed dead) to most-probable. The conflict between these two goes back to when Sandor Clegane was caught playing with his older brother Gregor's toys. Gregor grabbed his head and held it in the coals of the fire, scarring the face of his younger sibling. Both Cleganes grew up big and mean and earned nicknames based on their actions: Gregor became The Mountain because of his immense size, and Sandor became The Hound because of his unquestioning obedience and fierce demeanor.

Fans have long wanted to see the brothers face off in battle and that desire only intensified as the show leaned heavily into The Hound's redemption arc, after being left for dead by Arya Stark. It's suspected that a gravedigger in the novels is actually Sandor Clegane in hiding, but that has yet to be revealed. In A Dance With Dragons, the resurrected Gregor Clegane hasn't been officially identified, instead, he is introduced as Ser Robert Strong, a silent and unsleeping servant of Cersei. Since the show revealed both the gravedigger and Ser Robert Strong as the Clegane brothers, fans have speculated about just how these two will meet in combat.

One popular theory suggests that the story of stolen toys is entirely false. Instead, The Hound, now a servant of The Lord of Light on the show, originally saw Gregor's ultimate fate — that he would be killed in a dual with his brother — in the flames as a child. Gregor was so enraged, he held Sandor's face in the embers, scarring him for life. Fans of this theory, and Cleganebowl, in general, were excited in the Season 7 finale when The Hound told his undead brother: "What did they do to you? Doesn't matter. That's not how it ends for you brother. You know who's coming for you. You've always known."

Lady Stoneheart Is In A River, Any River!

Given the adaptation choices thus far, it seems unlikely that we'll be returning to Catelyn Stark — killed at the Red Wedding after seeing her son and her daughter-in-law murdered by oath-breaking Freys. But in the novels, she does not go out unavenged. Pulled from the depths of the river where they dump her body, Catelyn Stark comes back from the dead as Lady Stoneheart to take vengeance against oath-breakers and Freys.

Since the Red Wedding, fans have hoped to see Lady Stoneheart appear on the show, waiting with bated breath every time a scene after the Red Wedding took place near a river. With the show version of Arya Stark already back in Westeros after her Faceless Man training and taking out the entire male Frey line to avenge her brother, it looks like Lady Stoneheart's purpose in the story is being fulfilled by a living Stark. Which makes good sense — how many resurrected characters can the narrative ultimately take?

<p>Maisie Williams as Arya Stark, <a href="https://www.tvguide.com/tvshows/game-of-thrones/305628/"><em>Game of Thrones</em></a> </p>

Maisie Williams as Arya Stark, Game of Thrones

Jaqen H'ghar was Syrio Forel

In Season 1, when Arya is taken to King's Landing with her father, Ned gifts her "dancing" lessons with Syrio Forel, the former first sword of Braavos. Syrio treats young Arya with respect and teaches her well before he appears to die defending her. We don't actually see Syrio's death, and we don't see his body or severed head later on; he's last seen in a room with several armed and armored guards with only a wooden training sword to defend himself.

Then, when Arya is running low on adult friends as she travels north to Winterfell, she rescues a prisoner being transferred from the black cells in Kings Landing north to the Wall. That prisoner ends up being Jaqen H'ghar, a "Faceless Man," who gives Arya the gift of three names of people he will kill to repay her for her kindness. Arya, Hot Pie, and Gendry escape from Harrenhal later on in the season after Arya uses some quick thinking to get Jaqen's help. The Faceless Man reveals that he can actually switch faces at will because he's an assassin trained at the House of Black and White. He gives Arya a coin that will allow her passage there should she ever decide to become an assassin herself — and, of course she does! Girl loves some vengeance.

The fan theory suggests that there actually was a First Sword of Braavos name Syrio Forel and he eventually traded his face to the House of Black and White at the end of his life (the House of Black and White is also located in Braavos). Then, Jaqen H'ghar would be able to make use of his face while in King's Landing.

<p>Tyrion Lannister (<a href="https://www.tvguide.com/celebrities/peter-dinklage/169904/" target="_blank">Peter Dinklage</a>) in <em><a href="https://www.tvguide.com/tvshows/game-of-thrones/305628/">Game of Thrones</a>.</em> </p>

Tyrion Lannister (Peter Dinklage) in Game of Thrones.

Tyrion is a Targaryen

The origins of this fan theory go back to the shortest and youngest Lannister's tumultuous relationship with his "father" Tywin Lannister. Fans of this theory think that Tyrion is actually the son of the Mad King Aerys Targaryen, who was infatuated with Tywin Lannister's wife, Joanna. Before the sacking of King's Landing when Tywin turned on the Mad King, the two had an uneasy alliance made worse by Aery's attraction to Tywin's wife.

We've seen on the show, and it is equally evident in the novels, that Tywin had a deep hatred for Tyrion, often denying him consideration for his Lannister birthright or giving him the lowliest of tasks that could be held by the noble family. Tywin's final denial that Tyrion was "no son" of his read as literal (as well as a deeply cutting insult) to a few fans. That would also mean that Tyrion shared the Targaryen blood that allow Daenerys and Jon Snow to have a special relationship with dragons, something we saw Tyrion demonstrate when unchaining the dragons in Meereen.

Timeless Bran (Bran is all Brans)

This fan theory suggests that the Three-Eyed Raven state that Bran has been evolving towards will soon allow him to be "All the Brans," or every significant Brandon Stark that has popped up on the TV show's timeline.

There are three Brandons of note in Game of Thrones: Bran the Builder, or Brandon Stark who founded Winterfell and built The Wall to separate the White Walkers and The Children from the realms of men. There's Ned Stark's brother Brandon, who was killed by The Mad King, helping to pull Ned Stark into Robert's Rebellion. And, there is Brandon Stark, sister of Sansa and Arya.

When the show revealed that Bran could create closed time loops in his visions (by sacrificing poor Hodor in two time periods), this theory suddenly became more plausible. The Bran Stark that we're seeing on the show could have needed to be all the Brandon Starks to ensure events leading up to the showdown against the Night King turn out the right way.

Fans of this theory point to a passage in the first novel, A Game of Thrones, that might be George R.R. Martin foreshadowing the possibility of this theory years ago:

"I could tell you the story about Brandon the Builder," Old Nan said. "That was always your favorite." Thousands and thousands of years ago, Brandon the Builder had raised Winterfell, and some said the Wall. Bran knew the story, but it had never been his favorite. Maybe one of the other Brandons had liked that story. Sometimes Nan would talk to him as if he were her Brandon, the baby she had nursed all those years ago, and sometimes she confused him with his uncle Brandon, who was killed by the Mad King before Bran was even born. She had lived so long, Mother had told him once, that all the Brandon Starks had become one person in her head.

Game of Thrones returns April 14 on HBO.

Dave Gonzales is a pop culture commentator and co-founder of the Storm of Spoilers podcast about Game of Thrones.

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