Robin of Sherwood by Michael Morpurgo
This original, dramatic retelling is told as a flashback: after a storm a boy discovers a great oak tree has fallen. Beneath the disturbed roots he finds a hunting horn, bones and a skull. Clutching these objects, he has a dream, and relives Robin's story. He enters the dream world of Sherwood forest where he leads a band of albinos and misfits to fight against the Sheriff's injustice.