
From the New York Times bestselling author of The Sisters Grimm and The Weirdies comes the third and final book in this wildly imaginative middle-grade adventure series with aliens, robots, and an epic battle for earth that might just be won with a slip-and-slide...

From the New York Times bestselling author of the Sisters Grimm and NERDS comes the third and final book in the time-jumping, universe-skipping, action-packed middle grade series with equal parts humor and heart! After his adventures...
