This book is about friends Andy and a Terry that live in a really cool 13-storey treehouse, with cool things like a bowling alley, games room and secret lab. They invent things and write things; Andy does the writing and Terry does the pictures. I could read this book on my own without assistance. I read it pretty quickly as it was really interesting and funny, so I wanted to keep reading it. I liked there was chapters, so I could read to the end of the chapter and knew where I was picking up, and each chapter was a good length. I liked at the end of the book there were fun things to do; a word search, maze, spot the difference, a quiz and jokes. The black and white illustrations helped bring the book to life. Chapter 7 the monster mermaid, maybe be scary to some readers.

The pictures of the monster aren't really scary, but what is written might scare some; talks about eating people, but goes into detail; ripping limbs, crushing heads etc, so a bit gruesome. One chapter has one word all the way through, which was silly but funny. The friends get up to some crazy things, an enjoyable book.