So, Jon Snow appears to have died at the end of the fifth season of Game of Thrones, stabbed by his fellow sworn brothers.
There are some interesting theories that suggest he's not – perhaps he warged into Ghost, perhaps his (alleged) Targaryen side will come out, or perhaps he'll even come back as a White Walker.
There are just too many loose ends to tie up.
And sure, Kit Harington might have said he's done with the show, but if he isn't... wouldn't he have to say that anyway?
So, how can his apparent death not be the end? One leading theory is that Melisandre's return to the Wall is incredibly important.
As a priestess of the Lord of Light, she is a practioner of a religion known to be able to raise the dead. Earlier in the series, she met the Red Priest, Thoros of Myr, who was at the time leading the Brothers Without Banners.
So, resurrection can occur in the world of Game of Thrones, at the behest of followers of the Lord of Light. But why would Melisandre bring Jon back?
One of the major reasons Jon might not be done is that it's possible that Jon is Azor Ahai reborn.
Milllennia before the series begins, there was a period when the White Walkers attacked the Seven Kingdoms, before being driven back by a single hero, known as Azor Ahai, after which the Wall was built as a defence. Now the White Walkers are moving again and winter is coming, Westeros is due a new hero.