The Flash" season 3 is going to dive immediately into the events that happen due to Barry Allen aka the Flash (Grant Gustin) going back in time to alter history. A brand new trailer has revealed that he may not even want to change time back to its original state due to the presence of Wally West as Kid Flash (Keiynan Lonsdale).

The trailer, dubbed the "Run Devil Run" promo, shows Barry revealing to Wally that in the original timeline he was the Flash but in this world, he no longer has to be the hero because Kid Flash is there. Wally then tells him to not call him Kid Flash.

Iris (Candice Patton) is also shown, and in the beginning of the trailer, it is hinted she barely even knows Barry in this timeline. However, later on, she tells the group that Barry is the Flash, and she may have learned about the way the events were supposed to happen.

Up to this point, it is shown that Barry may want to keep things this way as he no longer needs to sacrifice his time and effort to become a superhero since both of his parents are alive, and everything seems to be perfectly fine. However, the trailer then reveals Reverse-Flash (Matt Letscher) and the Rival (Todd Lasance) causing trouble.

The Rival, in the original comic books, is an enemy from the Golden Age of DC comics. He was a rival of Jay Garrick (John Wesley Shipp). He was later trapped in the Speed Force, and it is hinted that Barry's decision to alter time may have freed the Rival from imprisonment.

Kid Flash and the Flash team up to fight the Rival, but, in another clip, the Flash is shown experiencing some sort of a headache and breakdown. When he approached Reverse-Flash to explain what is happening, it is revealed that he is slowly forgetting the original timeline, and he must choose which timeline he will want to preserve.

"The Flash" season 3 is scheduled to premiere on Oct. 4.