North of the Wall was full of surprises this episode. After that unpleasant look at the mutineers at Craster's Keep, we are taken even farther north as we see a lone figure riding a horse in the distance. It is revealed to be a White Walker, and he is carrying the baby Rast left out for sacrifice. He makes his way up a mountain where he places the baby on a slab made of ice. Another White Walker with horns on his head walks forward and picks up the baby. He places a finger on the baby's cheek and his eyes turn blue. This scene had show watchers and book readers alike genuinely surprised. For the first time, the show has given the audience information the the books have yet to divulge. Not only do we now know what the White Walkers do with Craster's babies, but we have been given a glimpse behind enemy lines, which gives rise to questions. Is that mountain their fortress, and if so, how far north do the White Walkers dwell? Who is the horned White Walker? Is he the king? The show has now officially revealed more about the White Walkers than the books have, even if it's just a little. This scene marks a new era for the show; one where it is no longer beholden to the structure of the books. It is clear that the showrunners are pulling from future material to keep the narrative from dragging, as becomes the case in later books meaning that us smug book readers can be just as surprised as everyone else. Who knows what we'll see in future episodes...
