WALT AND WHITTY AND PB tumble through time. Walt stretches out his legs and glides down, pretending he’s a paper airplane. Whitty screams and clucks and flaps his wings, terrified. PB somersaults. They fall past kids with big hair playing Pac-Man in the eighties. They fall past families eating fondue, listening to Peter, Paul, and Mary sing “Puff, the Magic Dragon” in the seventies. They fall past tie-dyed teens playing Twister and watching Star Trek on TV in the sixties. They fall past a five-year-old girl in a poodle skirt riding in the back of her daddy’s T-Bird convertible, singing along to Buddy Holly in the fifties.