The most memorable moment on the Game of Thrones season six premiere doesn't have to do with Jon Snow at all — though we do find out what's up with him. In a bizarre twist at the end of the episode, Melisandre slips out of her cloak and chunky necklace and is suddenly old AF. (And I say that with total respect for the elderly.) While you may have been shocked, we probably should have seen this coming. "There have been a few hints before that Melisandre is much older than she appears," said producer/writer David Benioff in HBO's Inside the Episode. "Going back to a very early conversation with George R.R. Martin about her, she is supposed to be several centuries old." Interesting! There are some more great tidbits in here; just watch until the end.
In terms of the technicalities of that final moment, the look was acheived through the use of facial prosthetics for actress Carice van Houten, while her head was superimposed on an older woman's body. Entertainment Weekly interviewed director Jeremy Podeswa about the episode, and he said the producers didn't want to pinpoint a specific age for Melisandre: "The idea is there's an indefinite indeterminate quality that she could be ancient. We were limited by choosing to use a real person rather than a complete CG creation. Because what does a 400-year-old person look like? We don't know. So if you try to create that, then you're creating something that looks beyond our known reality. Here you feel like she's very old without putting a number on it."
We really should have seen this coming since season three, when Melisandre tells Gendry that she had been born a slave. When she was sold, she would have been branded on her face, yet have you seen any scars on her ivory skin? This would suggest that she has been using magic to conceal parts of her previous appearance for years. Going back to season two, the necklace begins to glow when Melisandre takes poison, signaling that it is linked to her body in some truly mysterious ways.
Let's hope we'll get some more answers this season!