All the Heroes in the DC/CW Universe must team up to defeat a menacing alien threat.
When the Dominators attack Central City, the Flash enlists the Green Arrow to help stop them, but the battle requires them to track down the Legends of Tomorrow and bring Supergirl as a secret weapon.
Director: Dermott Downs
Writers: Greg Berlanti (developed by), Andrew Kreisberg (developed by)
Stars: Grant Gustin, Candice Patton, Danielle Panabaker