When Barry Allen wakes up at his desk, he discovers the world has changed. His mother is alive and old allies are now strangers. It's a world on the brink of a cataclysmic war - but where are Earth's Greatest Heroes to stop it? It's a place where America's last hope is Cyborg, who's attempting to gather the forces of The Outsider, The Secret 7, S!H!A!Z!A!M!, Citizen Cold and other new and familiar-yet-altered faces! It's a world that could be running out of time, if The Flash can't find the villain who altered the timeline!