The Mysterious Benedict Society by Trenton Lee Stewart (Paperback)

When a newspaper ad invites gifted children to take a series of strange tests, four very different kids pass and are recruited for a secret mission. Reynie, Sticky, Kate and Constance must go undercover at a mysterious institute and stop a dangerous plot, using only their wits, their teamwork and a lot of courage.

The first book in Trenton Lee Stewart's bestselling series is packed with puzzles, riddles and clever twists, and inspired a television adaptation.

A great pick for middle grade readers who love mysteries, brain teasers and stories about friendship.