‘Arrow’ Season 2 Episode 8 Spoilers: When And Where To Watch ‘The Scientist’ Online And On TV [VIDEO]

"Arrow" returns with episode 9 of Season 2 on Wednesday night when "The Scientist" airs at 8/7c p.m. on the CW. According to an official synopsis of tonight's episode, viewers will meet Central City assistant forensics investigator Barry Allen as he offers to help Oliver and the team with cracking the code of a seemingly impossible robbery at the Applied Sciences Division at Queen Consolidated. Oliver will sense that there's more to Barry Allen than meets the eye. Scroll down to the end of the page to check out a preview clip as well as a link to the episode after it airs.

"Barry comes to Starling City because there is an unexplained robbery at Queen Consolidated and Barry is very interested in the unexplained for reasons that we will find out over the course of these two episodes," executive producer Andrew Kreisberg told TVGuide.com at a screening on Monday. He added that this pre-Flash Barry is in many ways the polar opposite of Oliver. "Barry is outgoing and funny and a little bit unsure of himself and smart and is a squeaky wheel," Kreisberg said. "The contrast between Stephen and Grant is both comical and fun and has been really great to watch."

Barry was originally slated to return farther on down the line -- in Episode 20, which will now serve as a backdoor pilot for what could be a Flash spinoff. Barry Allen will now be getting his own pilot. "Episode 20 will just be an episode of 'Arrow,'" Kreisberg said. "In doing the backdoor pilot, we actually made it a little bit harder because we were going to have to take a right turn from where we were in our ongoing story to incorporate that. In some ways, this has freed us to take the Flash and just do the Flash separately and stay on a straight line."

The Huffington Post writes that tonight's episode will likely send the "Arrow" message boards into an eruption of activity. "Gustin's scenes with Emily Bett Rickards, who plays tech genius and Oliver Queen confidante Felicity Smoak, throw off a lot of sparks," writes the site. "But Rickards, "Arrow's" crucial secret weapon, also has great chemistry with star Stephen Amell and with David Ramsey, who plays John Diggle (Oliver's bodyguard and the third member of the show's core trio -- both Diggle and Felicity know about Oliver's crime-fighting alter ego)." Hit the box below to check out a promo clip for tonight's episode, and tune in to the CW at 8/7c p.m. to watch it as it airs. Can't make it to a TV at that time? Don't worry: you can click HERE to catch the episode online after it airs.