I’m always looking for books that would interest preteens and it’s quite hard to find good ones for that age group. I came across William Graham’s Danny Boyle series and fell in love with the characters, the setting, and the adventures. This book has everything a preteen looks for in a story: great characters, action, adventure, and a believable story. Danny Boyle is a twelve year old boy who is always looking for adventure. When his uncle tells him about a world under the ground he decides to find it and enlists the help of his best friend, Chip. Unfortunately, his little sister secretly follows them and gets herself kidnapped. They all end up not only finding the world under the ground but fighting in a war between the two tribes who live there. I enjoyed reading this book. The characters are completely believable for their age group. The author has done an excellent job of writing for and about ten to twelve year olds. The relationship between Danny and his sister reminded me of my relationship with my older brother. The book is short, around one hundred pages on my ereader, so it’s perfect for blossoming readers. I read the digital form of this book and it formatted well. For me the cover wasn’t all that interesting and may need to be a little more eye catching to grab a preteen’s interest but the story was excellent.