This is one of the series of "Great Illustrated Classics," and is slightly abridged as compared to the original version.  At 238 pages, including many illustrations, you might think the editors took out a lot.  Still, it is surprisingly exciting.  This book is an interesting collection of three Sherlock Holmes stories, each a separate mystery.  In the first story, red-headed people are involved in a charity group.  Only red-headed people can join, and they are well-paid for their work.  The charity is mysteriously closed suddenly.  You'll have to read the rest to see why. 

The second story is the strangest and the most frightening of the three.  In this one, a young girl dies, but no one knows why or how.  Her stepfather collects exotic pets from India, such as a wild baboon, a cheetah and a snake.   Of course, Holmes figures out how the girl died. 

In the third story, "The Adventure of the Copper Beeches," there is a secret room in a large house.  The room is always kept locked, and the house is guarded by a large mastiff, an aggressive dog.  Holmes is called in to find out what secret is behind the door.

I think  this book is exciting and addictive.  Once I was in the middle of one of the stories, I couldn't put the book down. I found myself going back and rereading many parts of it because it was well-written.  I would recommend this to someone 9-12 years old who likes books that are mysterious and chilling.  This collection of Sherlock Holmes stories made me want to read more of his works. I hope you like this book as much as I did.