Flashpoint

Follows Barry Allen's realization that his world is not as he has known it, with certain details being "off." His long-dead mother is alive, many of his superpowered colleagues are different in subtle and not-so-subtle ways, and he himself is without his speedster abilities. As Barry unravels the mystery, he discovers there's a limited window of time in which to set things right, or else the alternate reality will permanently supplant his own.