Gabriel Silk s father is Keeper of the Cloak. The Silks have been keepers since their ancestor left it in the care of their family 900 years ago. The cloak must never leave the keeper.. When Gabriel s father attends an Alchemists convention in Belgium, responsibility for the cloak falls to Gabriel. But when Gabriel is sent to stay with his uncle, he is intercepted by those with evil designs on the cloak and a long and difficult journey ensues.