Nancy Drew Series by Carolyn Keene

Nancy Drew is a teenage detective who will not let any question rest unanswered. Along with the occasional help of her friends she strives to gain the truth even if it means potential danger or death.
When a little girl named Judy bangs her head on a rock Nancy's first adventure begins The Secret of the Old Clock, can she discover the truth?

Carolyn Keen is the author of the Nancy Drew series and The Dana Girls . With the success of  The Nancy Drew novels Carolyn Keen also wrote The Nancy Drew Spinoff, River Heights and the Nancy Drew Notebooks.

Personally I find Nancy a perfect character of the book as she is brave, strong and determined all good character traits for a detective and also a personality you can look up too and sympathise with.