The Unwritten (Volume 4) (Leviathan) - Mike Carey

This fourth volume in the acclaimed series sends Tommy Taylor into the world of Moby-Dick! After the shocking return of Tommys father, best-selling fantasy author Wilson Taylor, the mysterious Cabal audition a new assassin and Tom seeks out the source. The source of what? Hes not really sure, but it looks like a whale, and apparently it can be found in the Nantucket farmhouse where Moby-Dick was written. What he finds is a path into a whole different ocean, with more trouble (and more whales) than he could possibly imagine.