The Flash has released the first synopsis for its "Armageddon" five-part story arc.

According to The CW, Part One of the Season 8 premiere will see the Scarlet Speedster and his team face off against "a powerful alien threat" that "arrives on Earth under mysterious circumstances." To stop it, the Flash will seek out help from some old friends to save the day. Brandon Routh will guest star in the episode, reprising his role as Ray Palmer/the Atom. "Armageddon, Part 1" will air on Nov. 16.

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Routh first joined the Arrowverse in Season 3 of Arrow, playing Dr. Ray Palmer, a genius industrialist and the new CEO of Queen Consolidated. He eventually became the size-shifting superhero the Atom. Ray went on to join the cast of Legends of Tomorrow as a regular character until he left the show in the fifth season, with his character marrying the reformed witch Nora Darhk (played by Routh's actual wife, Courtney Ford).

Other returning players in "Armageddon" include Cress Williams as Jefferson Pierce/Black Lightning from Black Lightning, Chyler Leigh as Alex Danvers/Sentinel from Supergirl, Katherine McNamara as Mia Smoak/Green Arrow from Arrow, Javicia Leslie as Ryan Wilder/Batwoman from Batwoman and Osric Chau as Ryan Choi from the "Crisis on Infinite Earths" crossover. Additionally, two classic Arrowverse villains will make their return in "Armageddon": Tom Cavanaugh as Eobard Thawne/the Reverse Flash and Neal McDonough as Damien Darhk. The pair will join the crossover's new villain: Despero, played by Tony Curran.

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Eric Wallace, who wrote the first part of "Armageddon" and serves as showrunner on The Flash, said of the crossover, "Simply put, these are going to be some of the most emotional Flash episodes ever. Plus, there are some truly epic moments and huge surprises that await our fans. And we’re doing them on a scale that's bigger and bolder than our traditional Flash episodes. So yes, 'Armageddon' is a lot more than just another graphic novel storyline. It’s going to be a true event for Flash and Arrowverse fans, old and new. Honestly, I can’t wait for audiences to see what we’ve got planned."

The full synopsis for the Season 8 premiere of The Flash reads as follows:

“Armageddon, Part 1” — (8:00-9:00 p.m. ET) (TV- PG, LV) (HDTV)

PART ONE OF THE ARMAGEDDON FIVE EPISODE EVENT – When a powerful alien threat arrives on Earth under mysterious circumstances, Barry (Grant Gustin), Iris (Candice Patton) and the rest of Team Flash are pushed to their limits in a desperate battle to save the world. But with time running out and the fate of humanity at stake, Flash and his companions will also need to enlist the help of some old friends if the forces of good are to prevail. Brandon Routh guest stars.

The episode airs Nov. 16 on The CW.

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Source: The CW