When Barry and Iris deal with the loss of their daughter, the team faces their greatest threat yet - one that threatens to destroy all of Central City; Killer Frost has a brush with death that will change her relationship with Caitlin.
6x02 - A Flash of the Lightning
Faced with the news of his impending death, Barry's resiliency suffers as he struggles to fight fate; Cecile's career as a D.A. conflicts with her identity when she crosses paths with a villainous meta-human.
6x03 - Dead Man Running
Barry prepares a member of Team Flash for life without him while hunting a terrifying meta-human with an unquenchable thirst; Ralph uncovers a family secret.
6x04 - There Will Be Blood
Barry's efforts to prepare Cisco for Crisis are derailed when Cisco schemes to save Barry's life instead; Ramsey Rosso uses his deadly new abilities to save his own life while sacrificing his humanity in the process.
6x05 - Kiss Kiss Breach Breach
Cisco's faith in his ability to fill Barry's shoes as Team Leader is upended when he learns of a shocking murder; Killer Frost trusts no one except herself to hunt down the dangerous Ramsey Rosso.
6x06 - License to Elongate
Barry turns his attention to prepping Elongated Man for life after Crisis and without The Flash, but Ralph ultimately teaches Barry a lesson. Meanwhile, Cecile faces her own moment of self-discovery while helping a recuperated Chester P. Runk reclaim his identity.
6x07 - The Last Temptation of Barry Allen, Pt.1
As Barry stands on the threshold of his impending death in Crisis, his convictions are tested when the monstrous Dr. Ramsey Rosso infects The Flash with a mysterious, hallucinogenic contagion. Meanwhile, Iris uncovers a vast conspiracy.
6x08 - The Last Temptation of Barry Allen, Pt. 2
With the Flash battling Bloodwork, Iris and Cisco fight to help Barry take control of himself before he's lost forever; the rest of the team fight to reclaim control of Central City from Bloodwork's growing army.
6x09 - Crisis on Infinite Earths: Part Three
Pariah enlists Black Lightning to help stop the Anti-Monitor after the Flash of Earth-90 shares what he learned from his battle in 'Elseworlds'. With the help of Black Lightning, Barry, Cisco and Killer Frost come up with a plan that could save them all. Meanwhile, Iris has a heart-to-heart with Ryan Choi while Oliver and Diggle return to an old familiar stomping ground.
6x10 - Marathon
The Citizen prints an explosive story, Iris' life is threatened; refusing to hide from her attackers, Iris sets out to expose a dangerous organization; Barry must face consequences of the crisis and fulfil Oliver Queen's wish for him.
6x11 - Love Is A Battlefield
Barry and Iris plan a romantic dinner for Valentine's Day but their evening is interrupted by an old foe - Amunet; Frost gets into the holiday spirit and attempts to help Allegra reconnect with an old love.
6x12 - A Girl Named Sue
After months of searching for Sue Dearborn, Ralph gets a lead on her whereabouts and finally comes face to face with his missing client. However, Sue refuses to return home to her family, and instead, takes Ralph on a daring adventure. Iris faces a new challenge while Barry considers a potentially dangerous request from a trusted source.
6x13 - Grodd Friended Me
Feeling overwhelmed with all the changes since Crisis, Barry conducts an experiment that goes awry and puts him directly in Gorilla Grodd's path; Iris works with Eva to escape the Mirrorverse.
6x14 - Death of the Speed Force
Kid Flash returns to Central City with a Zen attitude and new tricks up his sleeve. While thrilled to see his family again, Wally confides to Barry that he returned because he thinks there is something wrong with the speed force. Meanwhile, Cisco returns from his fact-finding mission across Earth-Prime.
6x15 - The Exorcism of Nash Wells
The Flash takes on a dangerous new meta named Sunshine; Cisco sets out to help Nash.
6x16 - So Long and Goodnight
After Black Hole hires Rag Doll to kill Joe, Singh suggests he go into the witness protection program; Ralph runs into Sue; Iris becomes suspicious of Eva.
6x17 - Liberation
After recent events, Barry takes a closer look at his life with Iris; Eva makes a bold move.
6x18 - Pay the Piper
Team Flash battle Godspeed and turned to an unexpected ally for help.
6x19 - Success Is Assured
Barry considers a risky plan to save Iris from the Mirrorverse; Ralph attempts to stop Sue from making a grave mistake that could destroy her life.
Overall: 8.5/10
After years of battling villains and repeatedly saving Central City, Barry and his wife Iris thought they could finally find time to enjoy being newlyweds, but their wedded bliss was interrupted by the appearance of their future daughter Nora West-Allen, who is a speedster known as XS, who has made a big mistake and needs her parents’ help to get home. With Nora in the picture, Barry and Iris’ lives are flipped upside down and, while Nora idolizes Barry and his legacy as The Flash, she carries with her a mysterious grudge towards Iris. Team Flash rallies to find a way to help Nora return to her time, only to discover her presence has altered the timeline and brought the early arrival of the most ruthless, vicious, and relentless villain Team Flash has ever faced: Cicada. They enlist the help of Sherloque Wells to aid in the search for Cicada, while Barry teaches a stuck Nora everything he knows about being a speedster and what it means to be a hero. Nora assists Team Flash with the take-down of a surge of new "meta-humans," but her place on the team is threatened when it is revealed that she is in league with none other than one of The Flash's earliest arch-enemies, Eobard Thawne. Ultimately, Nora is innocent in the grand scheme of Thawne's plan and helps Team Flash realize a way to defeat both Cicada and Thawne – yet, vanquishing their foes yields an agonizing loss as Nora erases herself from the timeline, leaving all of Team Flash devastated.
Reeling from the loss of Nora, Barry throws himself into work, defeating a record number of metas over the summer, while the rest of Team Flash deals with changes of their own – Cisco, having taken the meta-human cure, is no longer Vibe, Joe is now Captain of C.C.P.D., D.A. Cecile Horton is now considering leaving the district attorney's office, and Ralph Dibny is now searching for a missing heiress named Sue Dearborn. But all of that is put on hold when Dr. Ramsey Rosso, intent on curing death, is overtaken by his own desperation and ambition giving birth to a new villain, Bloodwork.