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 (Jessica Parker Kennedy), a speedster known as XS, who made a big mistake and needed her parents' help to get home. Team Flash rallied to find a way to help Nora return to her time, only to discover her presence had altered the timeline and brought the early arrival of the most ruthless, vicious, and relentless villain Team Flash has ever faced: Cicada (Chris Klein). They enlisted the help of Sherloque Wells (a master detective from Earth-221) to aid in the search for Cicada, while Barry taught Nora everything he knew about being a speedster and what it means to be a hero. As XS, Nora assisted Team Flash with the takedown of a surge of new metahumans, but her place on the team was threatened when it was revealed that she was in league with none other than one of The Flash's earliest arch-enemies, Eobard Thawne (The Reverse-Flash). Ultimately, Nora was innocent in the grand scheme of Thawne's plan and helped Team Flash realize a way to defeat both Cicada AND Thawne. Yet, vanquishing their foes yielded an agonizing loss as Nora erased 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 CCPD, D.A. Cecile Horton (Danielle Nicolet) is now considering leaving the district attorney's office, and Ralph Dibny is now searching for a missing heiress named Sue Dearbon. But all of that is put on hold when Dr. Ramsey Rosso (recurring guest star Sendhil Ramamurthy), intent on curing death, is overtaken by his own desperation and ambition giving birth to a new villain... Bloodwork.