After defeating the Reverse Flash once and for all, Barry Allen and Iris West-Allen are reconnecting and growing closer than ever before. But when a deadly group of Rogues descend on Central City led by a powerful new threat, The Flash and his team must once again defy impossible odds to save the day. But as The Rogues are defeated, a deadly new adversary rises to challenge Barry Allen's heroic legacy. And in their greatest battle yet, Barry and Team Flash will be pushed to their limits, in order to save Central City one last time.
S09E01
Barry creates a map book to guide him and Iris throughout their future in order to keep her safe, but the results are not what he expected, and instead, they relive the same day over and over again. Joe has a heart-to-heart with Cecile. A new big bad is introduced to Team Flash and friends and foes, old and new, begin to descend upon Central City.
S09E02
Barry feels guilty for what happened to Caitlin, and Mark comes up with a plan that makes everyone skeptical. Meanwhile, Red Death looms in Central City and commands that failure is not an option. Joe asks Cecile to make a choice that leads Cecile to think about the greater good. Allegra and Chester take a step in a new direction. Lastly, old friends pay an unexpected visit to S.T.A.R. Labs.
S09E03
Barry and Iris start to put together the pieces of what's happening in Central City and believe they know what the Rogues are after. Team Flash works together and recruits some unlikely allies to help, and the plan does not go as Team Flash expects. Meanwhile, Allegra does her best to avoid having a conversation with Chester.
S09E04
The Flash is forced to make an impossible choice. With the power out in the city, Team Flash calls upon the Rogue Squad to help as Iris is visited by an old friend. Joe and Cecile work on finding a balance.
S09E05
As the Red Death wreaks havoc on Central City, Barry and Iris come up with a plan and turn to Cecile for help. Barry is faced with what he thinks was his greatest mistake and the Red Death's greatest success. Khione wants to help Team Flash, but Barry can't risk losing her. Joe gives Barry a much-needed pep talk.
S09E06
As Barry and Iris prepare for their new life, luck changes for those in Central City. Cecile takes on a case with Allegra's help, involving a string of unfortunate – and highly unexpected – events. Meanwhile, Chester and the team work with Khione to figure out her abilities.
S09E07
Iris is visited by Nia Nal, as she needs Iris' help. When Iris and Nia fall into a fever dream and explore different possibilities for their lives, Barry, Chester, Allegra, and Cecile desperately try to help them. Meanwhile, Mark entertains Khione, but they have different ideas of what is fun, leaving Khione to feel that Mark is trying to make her something she is not.
S09E08
A seemingly simple mold inspection at S.T.A.R. Labs leads to unexpected time anomalies. Barry and Iris try to make sense of the confusion - and figure out how to get back to their reality. Chester admits a secret to Allegra, which makes things awkward between the two, and Allegra relies on Cecile to act as a buffer. Meanwhile, Khione meets with an old friend of Team Flash.
S09E09
Team Flash throws a surprise birthday party for Barry, but things go terribly awry when Ramsey Rosso crashes the festivities.
S09E10
As Iris receives word of a career milestone, Barry is suddenly nowhere to be found. In trying to get back home, Barry runs across many familiar faces. Khione continues to figure out her powers, and Chester works on a suit for Allegra.
S09E11
Iris is alarmed by Barry's disappearance and Cecile assures her everything will be ok, but does she know that for certain? Team Flash is affected by a mysterious substance and Khione develops a better understanding of what she can and cannot control.
S09E12
Team Flash works together to figure out how to protect Barry, all while being very careful who they trust. Cecile is skeptical of the plan after an unsuccessful attempt. Khione's confidence in Chester enables him to convince Cecile to try one more time.
S09E13
The Flash, the fastest man alive, is tasked with his greatest challenge yet, to save the timeline and save existence. Friends old and new gather for an epic battle to save Central City, one last time.