The Twisted Tree — Melanie James

After Aneth's best friend, Geoffrey, disappears, her search for him uncovers secrets she never dreamed could be true-fairies living in the Dark Forest, a magical Twisted Tree leading to a vast underground world of mystical creatures, and a tyrannical Dragon Lord. But when she tries to save the fairies from the Dragon Lord, she travels through the Twisted Tree and realizes that all she thought she knew of the fairies and Dragon Lord is not as it seemed. With her life and the lives of many others at stake, Aneth undertakes a dangerous quest to cut off the Dragon Lord from his ultimate source of power and defeat him once and for all. But will she be able to complete her quest before time runs out, or will she remain forever trapped in the world guarded by the Twisted Tree?