The Game of Thrones Season 2 finale (Episode 10: "Valar Morghulis") ended with a shock as poor Sam found himself surrounded by the walking dead in the wilds of the north. While book readers could easily parse what was going on, some TV fans were left confused. Were those the White Walkers? Something else? And what were they up to?

Well, we're here to help. So here's the deal, as far as we can tell based on our book knowledge — no spoilers beyond explaining that scene, we promise!

Most of the figures we saw were Wights. They are essentially zombies, the animated dead with the ability to attack; Jon killed one back in Season 1. As we saw during that fight, they are very  hard to kill — so far, the only weapon we've seen that works is fire.

But then there was the twisted white figures with glowing blue eyes, like the one who was riding the zombie horse and looked at Sam (which was an excellent image). That guy wasn't a corpse come to life, he was his own entity: A White Walker, also known as an Other.

The White Walkers are a thing of legend in Westeros, mythical monsters from the time of the Children of the Forest and the First Men. They bring death and destruction, and they are the ones that animate the Wights. We've seen glimpses of them before; most notably in the opening scene of the show, and when Jon saw Craster sacrifice his baby earlier this season. Clearly, they aren't quite as gone from the world as most of the realm thinks. That shouldn't be a surprise — a big theme this season has been the re-emergence of magic in Westeros (see also: Dany's dragons).

Here's a useful quote about the White Walkers from Game of Thrones (the book). Old Nan is describing them to Bran:

‘In that darkness, the Others came for the first time,’ she said as her needles went click, click, click. ‘They were cold things, dead things, that hated iron and fire and the touch of the sun, and every creature with hot blood in its veins. They swept over holdfasts and cities and kingdoms, felled heroes and armies by the score, riding their pale dead horses and leading hosts of the slain. All the swords of men could not stay their advance, and even maidens and suckling babes found no pity in them. They hunted the maids through frozen forests, and fed their dead servants on the flesh of human children.’

So, let's just say that an Other leading a horde of Wights is a very bad thing. The Wall was built specifically to keep this kind of threat contained in the North. Will the Night's Watch be able to keep the rest of Westeros safe, particularly with Mance Rayder's army of Wildlings also threatening to attack? That will probably be a plotline in Season 3.

Check out all of Wetpaint Entertainment’s Game of Thrones coverage.

Rebecca Martin is an editor at Wetpaint Entertainment. Follow her on Twitter @BeccaMartin47.

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