Of the pleasures denied, or at least postponed, in "Game of Thrones" is a deeper exploration of the Others, or White Walkers, those mythological half-dead, half-alive creatures of the land of perpetual winter who emerge ever so briefly from the windblown snow, like white shadows, then disappear again before anyone can think much about them or focus on them.
They inhabit the magical edges of this tale, appearing usually at the outset of seasons (or the second and third anyway), then are gone again. No one in the Seven Kingdoms is particularly worried about them (the Night's Watch is a different story), or even believe that they exist: They haunt children's dreams, not adult nightmares.
And then, the conclusion of Sunday night's "Oathkeeper," offering the deepest most sustained look at a walker yet in the series -- into their very eyes, as blue and frostbitten as you might imagine, in your "GoT" nightmares anyway.
Enter "Night's King," a self-appointed king, in fact, and progeny of an unholy union between man and walker, who carried the Craster's Keep baby to certain sacrifice, where another walker would apply his finger and render the child unto whatever alt-reality the wights and Others occupy.
It was a remarkable pull-back-the-curtains close that offered (finally) a focused look on their mystery and mythology -- a sacrificial circle, with Others (presumably) around the perimeter.
Walkers, or "Others," and wights probably posed a challenge for George R.R. Martin as much as David Benioff and D.B. Weiss; "Game of Thrones" doesn't luxuriate in the magical elements -- dragons included -- because they tend to disrupt the realistic ones: The battles between men, above and below the Wall, and the tangled affairs of those who would be king. That's what really drives the story, not the "magic," which operates by its own set of rules, logic and physics.
It's a balancing act that "GoT" has carefully maintained -- too much magic turns this into something entirely different, a cartoon even, because the rules that govern men become irrelevant or subsidiary to the rules that govern the mythical characters.
Sunday night, the appearance of the Night's King, who accepted the sacrifice, because that what he does. An original commander of the Night's Watch, he fell in love with a walker, who was to become his White Queen, "with skin as white as the moon and eyes like blue stars." He brought her to the Nightfort on the Wall, and ruled there for 13 years, until overthrown.
But he's still out there -- the Queen's whereabouts unknown -- and still offering sacrifices to his masters.
Now the questions: When will he appear next, and why baby sacrifices, and why not adult sacrifices, and how is he related to Bran, and what about "Coldhands" -- hands, fingers, limbs a preoccupation of "GoT" ... when will he make his entrance?
Then this: "GoT" is rich in foreshadowing. What does the fleeting appearance of the Night's King foreshadow?