Thanks to his abilities, Johnny's age was retarded, keeping his appearance younger and vigorous, despite his true age. After the Justice Society of America returned following a long absence, Johnny assisted them occasionally. Together with the Justice Society, Johnny would face the villain Extant during the time-event known as Zero Hour. Like the other heroes present, Johnny was aged considerably by the villain. Though he was now much older physically, he did not relinquish his hero-ing activities, and together with his daughter (now calling herself Jesse Quick) helped train the time-displaced Impulse.