Board Thread:General Discussion/@comment-4962906-20151007080647/@comment-6175354-20151007170810

CoolDudeAl wrote: Based on a future episode title, Nimue is probably who trapped Merlin in the tree. Nimue was the Lady of the Lake who imprisoned Merlin, in the legends.

Belle warned Hook, that it is easier to hate the Dark One than to love one. My theory.... Nimue was the love of Merlin's life, before she became the first Dark One. Merlin could not bring himself to destroy the Darkness, after Nimue completely embraced it. Being that the Darkness twists the hosts thoughts, Nimue punished Melin by trapping him within a tree.