Bartholomew 'Barry' Allen had a relatively normal life, until his father was wrongly accused for the death of his mother and imprisoned. Since then, he enrolled for a forensics scientist at Central City to try and uncover the truth. At one fateful moment while working overtime, Barry was hit by a lightning bolt while dowsed in chemicals, the result of this giving him super speed. He used this power to become The Flash, protecting Central City at every point in the day, due to him being able to go faster than the speed of light. This astounding potential of his powers is what landed Flash on the Justice League, becoming a founding member and a mainstay.

For the Primeverse version of Flash, you will need to emulate either Josh Keaton's performance as Spider-Man in Spectacular Spider-Man OR one of the actors who performed as Sonic the Hedgehog in the past (e.g. Ryan Drummond, Jason Griffith, Roger Craig Smith, and/or Ben Schwartz). However, for the Injustice Flash, you will need to also emulate a little bit of Grant Gustin's performances from the Arrowverse Flash series, as this is a Flash who is dealing with doubt about the Regime and whether they are on the right path or not. You may also refer to Roger Craig Smith's performance as Sonic in Sonic Frontiers for this role.