The Mysterious Benedict Society and the Prisoner's Dilemma is by Trenton Lee Stewart. The third book in the Mysterious Benedict Society series. An unexplained blackout occurs in Stonetown and the Whisperer is stolen. The four child find themselves embroiled in a final adventure to save everyone from Mr. Curtain and his evil minions. A very enjoyable book in an equally enjoyable series.
Ratings: 7th grade - 8 out of 10.