Thanks to my agent Jo Williamson, and my editors Rebecca Hill and Becky Walker, for guiding me through the difficult second book with aplomb. To Kath Millichope, Sarah Cronin and Becca Stadtlander for the gorgeous cover, type, design and illustrations. To Sarah Stewart, Stephanie King and Anne Finnis for edits and advice on the last drafts. To publicity and marketing mavens Amy Dobson, Stevie Hopwood and Alesha Bonser; plus the entire Usborne team – you’ve been a joy to work with once again. To my mum, dad, family and Michael – for driving me crazy and keeping me sane through the final push to finish – I love you all to the moon and back.

Originally I intended Jack to be a Dawkins, which is the real name of the Artful Dodger in Charles Dickens’s amazing Oliver Twist. Then on a whim – and a jackdaw pun – I changed it to Door, which is also a character name in Neil Gaiman’s brilliant Neverwhere. So thanks to those two fantastic writers for unknowingly providing me with half a name each; plus every other awesome author who’s inspired me over the years.

Finally, I’d like to thank the stellar bloggers, librarians, teachers and many young readers who’ve told me how much they adored Cogheart, I hope you feel the same way about this one!