The new edition of "Sherlock Holmes and the Duke's Son" is part of the Oxford Bookworms Library, specifically designed for secondary school students and adults. This educational series offers a variety of classics, modern fiction, and non-fiction, categorized into seven reading levels from A1 to C1 of the Common European Framework of Reference (CEFR). The story revolves around Dr. Huxtable, who runs a boys' school in northern England. When the Duke of Holdernesse decides to send his son to the school, it is initially good news. However, Dr. Huxtable soon faces a serious situation when the duke's son is kidnapped. In his desperation, he seeks the help of the famous detective Sherlock Holmes to solve the mystery and rescue the boy. With a vocabulary of 5,800 words, this book is ideal for learners who want to improve their English skills in an entertaining way.