I finished the Citadel mission and appeared back in the Library. I accidentally left the library and appeared back in Stonemarket Plaza and had saved over my game. It was only then I remembered Garret mentioning going to the Forbidden Library to do something. I heard after that you get the mission for the Clocktower. I've gone back to Forbidden Library and nothing happens. Did I mess up and miss the Clocktower mission?
Did you read all the books and talk to everyone plus have you done the part with the ghost ship yet and the sewer and the estate on the island yet?These are all things that have to be done before the clock tower mission.