Tymon leaves his new home and his beloved Samiha to complete his Grafting studies with the famous Oracle of Nur. But Tymon and fellow traveller Jedda find that locating the Oracle in a corrupt and lawless city run by pirates and slave-drivers is no easy matter. Samiha's fate has been predicted by Grafters down the ages. When she is captured in Cherk Harbour and charged with grand heresy, there seems to be no way out...but Tymon does not believe in fate and is desperate to save her lift. As chaos hums through the Tree, survival revolves on the fate of just one.