William's Picks
The Mysterious Benedict Society by Trenton Lee Stewart
This book is about 4 kids: Constance, Reynie, Kate and Sticky.  Each of the kids has a special ability. They are recruited into the Mysterious Benedict Society by Nicholas Benedict.

Mr. Curtain runs a "school" and the kids have to find out what really happens there and stop Mr. Curtain. 

Same plot as before but not as good in my view.

They have to stop the villain (Mr. Curtain) from taking over the world. 

Same plot but best in the series.

Nicholas Benedict is the character who brought the four kids together. The book shows us how Nicholas Benedict is educated. 

This is a prequel to the Mysterious Benedict Society. It was my favourite.