The CW has released a preview for “Armageddon, Part 4”, the penultimate episode of The Flash’s five-part “Armageddon” event kicking off the series’ Season 8. The event has seen Barry Allen/The Flash’s (Grant Gustin) world turned upside down thanks to the arrival of the mysterious alien Despero (Tony Curran). Despero came hunting The Flash, claiming that in the future the speedster is the reason for the end of the world and last week, it was revealed that the reason why is that Barry loses his mind after enduring too much tragedy. In the upcoming “Armageddon, Part 4”, some unexpected old foes will return, specifically Eobard Thawe/Reverse Flash (Tom Cavanagh) and Damien Darhk (Neal McDonough). The episode will also see some more heroic familiar faces as well with appearances from Ryan Wilder/Batwoman (Javicia Leslie), Alex Danvers/Sentinel (Chyler Leigh), and Ryan Choi (Osric Chau).