So when it comes to writing fairytales how can I ensure those have hidden depths? By ensuring my characters have flaws the reader can identify with. By having subplots which are relevant to the overall plot, which complicate things for my heroine, which still need to be dealt with and in the meantime the main problem still needs to be sorted out. Rocket up the tension!
One thing I love as a reader is discovering the hidden depths in a story and trying to guess how it will effect overall plot. A great story will have layers to it and can yield up something new on repeated readings. Now there's a challenge to me as a writer!