This book genre is mysterious adventures, and it was written by Mary Pope Osborne. To state it briefly, in the beginning of the story the characters were looking for a tree house, and the tree house was in the middle of a forest. Once they found it they went inside and appeared in a ninja world. They had to follow a path, with the ninja. There was a samurai and an icy cold lake etc on the way. Towards the end, the samurai was coming so they hid behind a rock so they were not seen, and continued back home. Since you don’t know who the characters are then I will tell you more about them. The main characters are Jack and Annie. Jack is more of a reading guy, his favorite thing to do is read, that means he can get smart. Annie likes animals more than books. She loves taking care of what is around her. She is very careful with animals and nature. In addition Jack likes solving puzzles and mysteries. Two key events that happened in the book that added to the plot was. 1 Annie found a mouse that could help them accomplish their mystery, because the mouse was the key to finishing their misson. 2 the Ninjas in the story said there was a samurai. ( the samurai are dangerous.) Without the samurai the story would be less scary and curious. One of the main characters Jack, didn’t like nature, but in page #68 he changed, he started to like nature. He normally says,‘‘ oh brother’’ to his sister Annie, when she just wanted to take care of the little animals that she found, but this time when Annie, his sister was making a bed for for a mouse that helped them succeed in their mission, he kissed the mouse good night and started to change his attitude instead of saying, ‘‘Oh brother.’’ An unanswered question, I would like to ask is, do Jack and Annie’s parents know about their adventures while they are gone? Meanwhile,the thing I most enjoyed about the book was when the characters went to see the ninja master. That part was very mysterious. In the picture on that page, it looked like the ninja master was coming out of fog, but indoor fog. I liked that part because I love mysterious things. The last thing I would like to say about this book is that I would highly recommend this book a lot because even for kids, teenagers etc, for any person who doesn't like reading, this book can change your mind. Also, if you like reading that is even better because you will like reading more. I hope you will read my book someday, oh, and remember my book is called night of the ninjas.