Executive producer Greg Berlanti offers some differences between Arrow, The Flash TV series, Oliver Queen and Barry Allen.
Berlanti tells Digital Spy that The Flash will feature more of a science-fiction angle than Arrow as well as superpowers.
"Barry is different from Oliver," Berlanti said. "He's a man of science and has more of a sci-fi bent, whereas Arrow has a bit more of a crime bent. We've talked a lot on Arrow about the particle collider and Harrison Wells and S.T.A.R. Labs and so you'll see S.T.A.R. Labs as an active part of the show," Berlanti revealed, confirming that The Flash will feature super-powered characters.
Berlanti continues with mention how Barry Allen (played by Grant Gustin) is somewhat opposite of Oliver Queen (Stephen Amell.)
"We often talk about how Oliver comes off like a pessimist, but deep down he's an optimist and has hope," Berlanti offered. "Barry lost his mother at a very young age, his father was sent to prison for murdering his mom, he went through a lot of stuff - on the surface he's bubbly and upbeat and seems like an optimist, but deep down maybe there's no hope left."
Berlanti also said that if by chance The Flash TV series doesn't get picked up, Grant Gustin will be featured on further episodes of Arrow as Barry Allen.
"Arrow" airs Wednesdays at 8pm ET, with "The Flash" beginning production soon for a to-be-announced premiere date on the CW.
Check out Barry Allen's transformation to The Flash from Arrow: