The Book of Bill is a new companion book to the show Gravity Falls, focusing on the character Bill Cipher. The book will reveal Bill's origin story, his villainous agenda, and the secrets of the ...

Written by series creator Alex Hirsch, The Book of Bill is a humorous tie-in that reveals more about Gravity Falls and the mysterious Bill Cipher.

Alex Hirsch talks about Bill Cipher, Summerween, Gravity Falls, and which character deserves a 50 Shades of Gray-style spinoff. The Book of Bill is out now.