I read a book form a series called "The Hardy Boys" each book from the series has an mysterious for some detectives to solve.
Each book is about two detectives and their friends go though about to solve a mysterious cases and put out criminals that causes them.
I find this book is excellent.
The Hardy Boys (Hover)
Yeah, they were! I have two books form the series like you do already! One was called "The Waling Siren Mystery" and "The Arctic Patrol Mystery". Both of them are intersting! I was hoping to get more of these nice books.