WHEN 13-YEAR-OLD JOSH finds out he has to stay with his dad in Chicago for a few months, he’s not too thrilled. But when he arrives at the airport, he’s simply devastated. His father—who used to be a scatterbrained, but pretty normal, shoe salesman—has become a sideburn-wearing, hip-twisting, utterly embarrassing Elvis impersonator. Josh is determined to keep his dad’s identity a secret, but on his very first day at his new school, a note appears on his locker. It’s signed Elvisly Yours, and ins...