Crossover event featuring the first five episodes from the eighth season of the action adventure following the DC Comics superhero. After being struck by lightning and covered in chemicals while in his laboratory, forensic scientist Barry Allen (Grant Gustin) wakes up from a coma to find he has superhuman powers. He decides to use his new abilities to fight other superhumans created by the storm who are using their powers for evil in Central City. In this instalment, Barry and Team Flash take on an old enemy after alien Despero (Tony Curran) arrives from the future hoping to prevent Armageddon.