The Mysterious Benedict Society And The Perilous Journey by Trenton Lee Stewart

The Mysterious Benedict Society is back with a new mission, significantly closer to home. After reuniting for a celebratory scavenger hunt, Reynie, Kate, Sticky, and Constance are forced to go on an unexpected search--a search to find Mr. Benedict. It seems that while he was preparing the kids' adventure, he stepped right into a trap orchestrated by his evil twin Mr. Curtain. With only one week to find a captured Mr. Benedict, the gifted foursome faces their greatest challenge of all--a challenge that will reinforce the reasons they were brought together in the first place and will require them to fight for the very namesake that united them.