Last Sunday's episode of Game of Thrones ended with a scene that delighted both fans of the HBO series and the original books alike. The wight and White Walker attack on Hardhome was not seen in the books, and it's about time we saw these villains on the march. Their leader is equally fascinating — why is the Night's King on Game of Thrones so focused on Jon Snow? Granted, if that's who that spiny-headed creature is after all. There is a character in George R. R. Martin's A Song of Ice And Fire books called the Night's King, but he was defeated long ago. We don't know for sure if this is exactly the same guy. He does seem to fit the bill, and the icicles on his head do resemble a crown. We've also seen him once before — he's the same White Walker who we watched take one of Crastor's newborn sons as sacrifice and turn his eyes blue. What, are there no female White Walkers? Is there no end to the sexism in the Game of Thrones universe? (Someone should tell Arya about this. She'll know what to do.)

Still, there's no doubt that the guy was interested in Jon Snow. The two of them had quite the stare-down as he shrugged corpses back to life and Jon rowed away in a boat. In HBO's "Inside The Episode" clip for the episode "Hardhome," the creators simply stated that he was looking at Jon with intrigue. "This kid's actually possibly a threat for me," is his inner monologue according to D.B. Weiss. Not so fast — the simplest explanation may not be the most accurate. This is Game of Thrones, after all.

However, in the grand scheme of Game of Thrones, it's likely that there's more to it than that. Here are some theories as to why that guy was so intent on Jon Snow.

He Was Once Lord Commander

According to legend in the Game of Thrones world, the Night's King was the 13th Lord Commander of the Night's Watch. He fell in love with a white-skinned, blue-eyed woman, and left his post to live an evil life with her. So, does he see himself in Jon? Maybe that's it.

So, that makes two Lord Commanders who have fallen in love with a woman from beyond the Wall. The second, of course, is Jon Snow. The Night's King also shares some qualities with Mance Rayder, a former Watchmen who left to become King Beyond The Wall and lead the Wildlings.

He Was Once A Stark

The legend also speculates that he was a Stark named Brandon. Besides the little Lord currently hanging out with some Children in a tree, there have been a number of Brandon Starks throughout the years. There's the Builder, the Breaker, and, I don't know, probably a Candlestick-Maker as well. Anyway, can the Night's King sense Jon's Stark blood?

He Was Once Jon Snow

There's also a fan theory that the Night's King was a Stark bastard called Jon Snow. That's not too far fetched. Bastards, no matter who their father was, all share similar surnames based on their region. Snow, Waters, Stone, and Sand are just a few examples that we've seen in the series. The evidence that supports this theory is that Ygritte and the Wildlings think our Jon's name is "evil," and the implications of the old saying that "there must always be a Stark at Winterfell." Could a legitimate member of their original family be what has been keeping the White Walkers at bay?

He Can Tell Jon's A Secret Targaryen

Look, if the R+L=J theory is correct, someone else has got to know who Jon's parents are. There's no way that secret died with Ned Stark. In fact, I don't even think Ned thought he was the only person who knew. I just re-watched Season 1 of Game of Thrones and while Ned makes sure that he won't die with the secret of Cersei's children and their parentage, he doesn't send any ravens about his "own" bastard. What if the Night's King can sense not only the ice in Jon Snow, but also the fire?

He Is Jon Snow's Father

It's a little too Star Wars, so please forgive me. I had to suggest it.

He Has Heard Some Kind Of Prophecy

Okay, well now I'm in a Star Wars head space. It seems likely (for now) that Jon Snow will be able to unite the Wildlings and the Westerosi in the battle against the White Walkers. Restore balance to the Force and all that jazz — because it's pretty unfair now. An army that can take all the dead bodies from either sides of a battle, use them as unwilling recruits known as wights, and multiply exponentially is pretty depressing. What if there's a prophecy that refers to Jon Snow, and the Night's King suspects this?

Now, if only Jon could find a way to quickly burn casualties and ensure they don't come back. Do we know anybody on Game of Thrones with easy access to fire... maybe airborne?

He Hasn't Seen Valyrian Steel In A Long Time

That's the boring answer, of course. Jon wields a sword made from Valyrian steel, which is one of the few substances that can withstand the White Walkers' swords and kill them. Maybe he's just interested because he knows that Valyrian steel isn't forged anymore, and it's clearly a dangerous threat. The other two people on the show who have Valyrian swords, that we know of, are Brienne of Tarth and Tommen Baratheon, whose swords were forged from Ice, Ned Stark's weapon.

He Wants Jon Next

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Brace yourself: book spoilers are coming. It's definitely a possibility that the Night's King sees Jon as a potential new lieutenant. At the end of the last published novel, Jon Snow is stabbed and his fate unknown. Could Jon Snow become a White Walker, and potentially a villain? I'm going to need a lot of time to emotionally prepare for that.

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