This post contains spoilers for the Season 6 premiere of Game of Thrones.
The big twist at the end of "The Red Woman" was not that the episode's titular character was bringing Jon Snow back to life, as many hoped, but that she is actually much older than she appears.
When she removed her choker (which glowed red as she did so), she appeared elderly and frail, suggesting the necklace has the power to mask her true form.
But some fans have pointed out that in this scene in Season 4, Melisandre was taking a bath without her choker and still looked young and flawless.
The theory makes a lot of sense considering Melisandre is discussing the tricks and lies she uses to convert people in this scene, emphasising that Selyse doesn't need these because "you are strong enough to look into the Lord's light and see his truth for yourself. However harsh it is."
Still, this doesn't really explain why we as viewers see young Melisandre in this scene.
Not convinced? OK, OK, this theory might suit you better:
Reddit user I_Hate_Nerds comes to a different conclusion from the idea that Selyse is a "true believer" – that she (and therefore the viewer) is actually seeing Melisandre's ideal young and beautiful form even without the necklace due to the strength of her faith. If this is the case, it still ties in nicely with the idea that the big reveal happens at the moment when Melisandre's faith is lost.
Others still have speculated that the potion Melisandre pours into the bath is not your regular Lush concoction: It's part of the magic she uses to keep looking fresh.
Only time will tell if any of these theories are right, but the implications around the truth about Melisandre's faith and abilities could be huge for the fate of a certain bastard we all love.
vote votesThe necklace controls the glamour, but Selyse was seeing Melisandre's true form.
vote votesThe necklace enhances the glamour, but doesn't control it.
vote votesThe potion is what keeps Melisandre looking young.
vote votesThe show creators just flat-out fucked up the continuity.
vote votesI have another theory! (I'll share in the comments.)