Cavanagh has touched on a number of themes in his books. In his latest book, One Of Us is Guilty, we meet the billionaire Vanderpool family and are immersed in a gruesome murder. Cavanagh said he wanted to look at extreme power and wealth in America the influence of multi billionaires. For Cavanagh, this is a world away from his working class upbringing in Belfast. But he wants to reassure fans that Eddie Flynn will be back and hasn't been beaten yet.