That Grey Area - Book 1 - The girl from Otherworld

How far would you go for what you believe in?

Angels and Demons meets His Dark Materials - inspired by the Stanford Prison Experiment, the novel explores how normal people do evil. It's also about teenagers trying to find their place in the world (at least in their respective worlds) and discovering that 'being the hero' comes at a price.

When Stus became a member of the secret society of the Tree Circle, he knew he was not only becoming part of the Faerie elite, he was part of a force for Good. The Tree Circle's roots delve deep into Faerie, its branches shelter it from evils. Its members act in the shadows and none but the Oak Heart knows what terrible secret knowledge it protects.

But now the Oak Heart is dead and the knowledge he protected has gone missing. Stus must find it. At any cost - even human lives.

Lacie is not very good at meeting new people. In fact she's terrified of it.

Moving to France where she knows no one was hard enough, but when she is brought to a strange dream land full of magical folk, it is her worst nightmare. To make things worse, she learns she must help a boy with butterfly wings — wings! — solve riddles in order to retrieve a powerful knowledge held in a box. A knowledge left to him by his dying master together with a note with Lacie's name on it. But what help can she be, with no magical powers and no special talent?