Season synopsis
Contains spoilers for this season and earlier seasons.
After season 2's final choice to save his mother, Barry begins this season in the altered Flashpoint timeline, where he has both parents and Wally is Central City's Kid Flash. As Barry's memories of his old life fade and Wally is badly hurt, Barry releases Eobard Thawne to restore Nora's murder and return to his own time. The reset is imperfect: Joe and Iris are estranged, Cisco's brother Dante has died, and Barry must face consequences he cannot simply rewind. Alchemy starts restoring Flashpoint metahumans, while Caitlin develops cryokinetic powers and fears becoming Killer Frost.
Wally gains speed and joins Barry as Kid Flash, but Savitar manipulates him and escapes a Speed Force prison. Barry sees a future in which Savitar kills Iris, and the team tries to prevent it while dealing with Caitlin's transformation and Grodd's attack on Central City. After Wally is lured into the Speed Force, Barry enters to bring him back; Jay Garrick takes Wally's place so the younger speedsters can escape, leaving Jay imprisoned. Savitar uses Julian as a conduit and insists Iris's death is still coming.
The team learns Savitar is a future time remnant of Barry, created by a future Barry to fight Savitar; after surviving, the remnant was rejected by Barry's friends and ran back in time to become the armored enemy. He manipulates events to ensure Iris's death and his own creation. Before their final confrontation, H.R. uses a piece of Savitar's armor to find Iris and swaps places with her using a face-changing device. Savitar kills H.R. believing he has killed Iris, and Iris later shoots Savitar as he tries to kill Barry. With the threat ended, Barry enters the Speed Force to take Jay's place and contain the storm threatening Central City.