During Sam's early days at the Citadel, he is assigned to menial tasks. The only person who believes his account of the White Walkers' return is Archmaester Ebrose. However, Ebrose refuses to let Sam access forbidden textbooks to learn more about the White Walkers, as Ebrose does not consider them a threat serious enough to break with protocol. However, Sam steals a key to take the books back to his and Gilly's quarters. In reading the books, he discovers the location of a large deposit of dragonglass in a map of Dragonstone and sends word to Jon, now King in the North, of its existence.