The lightning key - Jon Berkeley

Now that Miles Wednesday has discovered his link to a magical Tiger's Egg, he's suddenly at the wheel of a great voyage. Determined to recover the stolen stone and free the trapped soul within, Miles sets off with Little, a Song Angel, and the wisecracking blind explorer Baltinglass of Araby. Their destination points far across sea and desert to the home of Miles's aunt Nura, who may be their only hope in releasing the Egg's true power. But along the way, their travels are riddled with thrills and near catastrophes - from soaring across the sky in an airborne schooner to run-ins with the twisted circus ringmaster, the Great Cortado, and his bumbling sidekick, Doctor Tau-Tau. Most threatening of all is a dark Sleep Angel who's descended from the Realm to seize the Egg and forfeit Miles's life. Will Miles crack the secrets of the Egg and stand up to the Realm in the face of grave danger? And will he ever be able to bring back his father?