‘The Flash’ Season 4 Plot Speculation: Team Flash Rescues Barry, Speedster Becomes Black Flash
It is a mystery what "The Flash" Season 4 will put Barry Allen through this time, although speculations are rife that he becomes Black Flash. This supposedly follows the "Rebirth" storyline in DC's comics.
"The Flash" Season 4 likely opens with Barry Allen back in Central City after his stay in the Speed Force. It has already been years since he left and a lot has happened (although he feels he only stayed for a day in the Speed Force). A new villain has been terrorizing Central City. Wally West and the rest of Team Flash are still around to protect the city and its people.
The consequences that led to Barry's return supposedly involve an intervention from his friends at S.T.A.R. Labs. According to Cinema Blend, it is likely that in "The Flash" Season 4 they pull him out, just as they rescued Wally in the past.
However, Barry has to pay the price for leaving the Speed Force. This is supposedly, where the "Rebirth" storyline comes in "The Flash" Season 4. In the DC comics, Barry returns to Central City but soon realizes that he is transforming into Black Flash. He decides to return to the Speed Force to spare his friends. There he meets another version of Eobard Thawne/Reverse Flash and learns that the latter is responsible for his transformation.
Barry becomes the new Black Flash after he gets charged with negative energy. It turns out that Reverse Flash created the energy. It remains uncertain though if "The Flash" Season 4 follows the Rebirth" storyline, since it would mean bringing back Thawne from the dead.
Regardless, one thing is certain to happen in "The Flash" Season 4. The synopsis from Fansided confirms the appearance of more metahumans in Central City. Barry and his friends at S.T.A.R. Labs continue to protect the city and its people from their threat.
The synopsis also confirms that Caitlin Snow continues to distance herself from Barry Allen and the team in "The Flash" Season 4. She remains as Killer Frost although a new version of the villain, one who has a conscience.