Agents of Light and Darkness: Library Edition

Taylor is the name. John Taylor....My card says I'm a detective, but what I really am is an expert on finding things. It's part of the Gift I was born with as a child of the Nightside - the hidden heart of London where it's always three a.m., where inhuman creatures and otherworldly gods walk side-by-side in the endless darkness of the soul. Assignment: Locate the Unholy Grail, the cup Judas drank from at the Last Supper. It corrupts all who touch it, but it also grants enormous power. So I've got some competition - from angels, devils, sinners and saints - in the search for the dark goblet.