Impulse and XS burst onto the scene in 2049! When Barry Allen and Iris West go out of town for a much-needed vacation, Bart and Nora are left to stay out of trouble in Central City. With their parents gone, Bart begs Nora to let him go on patrol and really be a hero, but Nora refuses, saying it's too dangerous without Barry there. But when one of Bart's classmates at Central City University starts causing trouble, how can Impulse not leap into action?