The Dragon Detective Agency is a series of children's books written by Gareth P. Jones and published by Bloomsbury Publishing. The first book, called 'The Case of the Missing Cats', was published in 2006. It involves a girl called Holly Bigsby who has lost her cat Willow. She calls the Dragon Detective agency but she does not know that there's a dragon on the other end called Dirk Dilly. Dirk thinks it is an investigation that he does not need to solve but he finds out there is a sinister plot behind the cat's disappearance. He and Holly become friends and she joins him on later cases.