Briony had always suspected there was something wrong with her teacher. But after doing some further investigation with her friend Sergio, she uncovers a secret conspiracy so amazing that she could never have believed it was true. Find out how the adventure unfolds in this thrilling mystery novel by Carnegie-medal nominee Annabel Pitcher.

* Diamond/Band 17 books offer more complex, underlying themes to give opportunities for children to understand causes and points of view.

* Text type: A mystery story

* Curriculum links: Citizenship

* This book has been quizzed for Accelerated Reader.

This book features in the following series: Collins Big Cat, Diamond Series .

This book is aimed at children in primary school. This book is part of a reading scheme, meaning that it is a book aimed at children who are learning to read. This reading scheme has multiple levels. This reading book uses the phonics method. This approach concentrates on teaching children how to map between sounds and spellings, allowing them to decode written words into their constituent sounds. Phonics skill thus involves being able to split the written word 'cat' into the phonemes /k/, /a/, /t/, and to map from letter 'c' to phoneme /k/, from letter 'a' to phoneme /ae/ and from letter 't' to phoneme /t/. Decoding skill is useful when reading unfamiliar words which use regular spelling sequences.

There are 56 pages in this book. This book was published 2013 by HarperCollins Publishers .

Annabel Pitcher studied English at Oxford and has since worked as an English teacher. She lives in Yorkshire with her husband and son, Isaac, and is now a full time writer. Visit Annabel's website at www. annabelpitcher. com and follow her on Twitter @APitcherAuthor. Collins UK has been publishing educational and informative books for almost 200 years.