I've just found out that Cobwebs in the Dark will be released on Wednesday 17th February, 2016! It should be available for pre-order a few weeks prior to that.
It's very exciting to think that three of the NightHawk Series will be out already and the fourth, The Girl in the Painting, is currently with my editor. I now need to decide whether there should be a fifth one!
As soon as the book is available for pre-order I shall put the link on the website.