The Camelot Spell (Grail Quest #1)
The quest for the Holy Grail sets out tomorrow, and all of Camelot is feasting well into the night- well, all of Camelot except for the servants like Newt and Ailis and the squires like Gerard, who are hard at work. Tragedy strikes, though, when, on the stroke of midnight, every adult in the castle falls into an enchanted sleep from which no one can awaken them; to make matters worse, Merlin (the king's enchanter) is gone and the only people who might know where to find him are bespelled. Newt and Gerard take it upon themselves to find Merlin, and Ailis, driven by a voice in her head, follows after them, but when they reach the enchanter he is less than helpful.
I first read this book when I was looking for a villainous Morgan le Fay to contrast with the classy and gracious librarian of the Magic Tree House books. I wasn't disappointed, though Gilman begins to deconstruct Morgain's character later on. By that point, I was older and wiser and no longer saw the character as the natural villain of the story.
Though I am in my late teens and enjoyed this book when I reread it, I would recommend that the average person beyond the age of twelve not bother- it's definitely a kids' book.