Someone hit me up on twitter last week asking what books exist in the Duffyverse. i.e. what books of mine exist in the same universe as Sean Duffy's universe. As you probably know Duffy has interacted with both Killian and Michael Forsythe who have novels of their own. One of Duffy's sidekicks is Alexander Lawson has also his own novel and I used to think that book took place in our universe but now its clear to me now that it doesn't. The Alexander Lawson of Hidden River is a detective operating in a universe without Duffy being there to guide him, the poor sod. Anyway these are the books - kind of - in the extended Duffy universe. All the characters in these books know and have interacted with Sean Duffy in some capacity. I haven't made a serious effort to tie in Fifty Grand and The Sun Is God but I reckon I cd if I worked a bit at it. But, anyway, this should be enough to keep you busy!