The Flash — “Flash vs. Arrow” Pictured: Grant Gustin as Barry Allen and Stephen Amell as Oliver Queen — Photo: Diyah Pera/The CW — © 2014 The CW Network, LLC. All rights reserved

The Flash — “Flash vs. Arrow” Pictured: Stephen Amell as Oliver Queen — Photo: Diyah Pera/The CW — © 2014 The CW Network, LLC. All rights reserved.

The Flash — “Flash vs. Arrow” Pictured: Grant Gustin as Barry Allen — Photo: Diyah Pera/The CW — © 2014 The CW Network, LLC. All rights reserved.

The Flash — “Flash vs. Arrow” Pictured (L-R): Grant Gustin as Barry Allen and Stephen Amell as Oliver Queen — Photo: Diyah Pera/The CW — © 2014 The CW Network, LLC. All rights reserved.

The Flash — “Flash vs. Arrow” Pictured (L-R): Emily Bett Rickards as Felicity Smoak, Tom Cavanagh as Dr. Harrison Wells, Danielle Panabaker as Caitlin Snow, and Carlos Valdes as Cisco Ramon — Photo: Katie Yu/The CW — © 2014 The CW Network, LLC. All rights reserved.

The Flash — “Flash vs. Arrow” Pictured (L-R): Danielle Panabaker as Caitlin Snow, Emily Bett Rickards as Felicity Smoak, and Tom Cavanagh as Dr. Harrison Wells — Photo: Katie Yu/The CW — © 2014 The CW Network, LLC. All rights reserved.

The Flash — “Flash vs. Arrow” Pictured: Tom Cavanagh as Dr. Harrison Wells — Photo: Katie Yu/The CW — © 2014 The CW Network, LLC. All rights reserved.

The Flash — “Flash vs. Arrow” Pictured: Danielle Panabaker as Caitlin Snow — Photo: Katie Yu/The CW — © 2014 The CW Network, LLC. All rights reserved.

The Flash — “Flash vs. Arrow” Pictured: Emily Bett Rickards as Felicity Smoak — Photo: Katie Yu/The CW — © 2014 The CW Network, LLC. All rights reserved.

The Flash — “Flash vs. Arrow” Pictured (L-R): Grant Gustin as Barry Allen and Stephen Amell as Oliver Queen — Photo: Diyah Pera/The CW — © 2014 The CW Network, LLC. All rights reserved.

The Flash — “Flash vs. Arrow” Pictured (L-R): David Ramsey as John Diggle and Emily Bett Rickards as Felicity Smoak — Photo: Diyah Pera/The CW — © 2014 The CW Network, LLC. All rights reserved.

The Flash — “Flash vs. Arrow” Pictured: Jesse L. Martin as Detective Joe West — Photo: Diyah Pera /The CW — © 2014 The CW Network, LLC. All rights reserved.

The Flash — “Flash vs. Arrow” Pictured (L-R): Grant Gustin as The Flash and Jesse L. Martin as Detective Joe West — Photo: Diyah Pera /The CW — © 2014 The CW Network, LLC. All rights reserved.

The Flash — “Flash vs. Arrow” Pictured (L-R): Grant Gustin as The Flash and Stephen Amell as The Arrow — Photo: Diyah Pera /The CW — © 2014 The CW Network, LLC. All rights reserved.

The Flash — “Flash vs. Arrow” Pictured: Stephen Amell as The Arrow — Photo: Diyah Pera /The CW — © 2014 The CW Network, LLC. All rights reserved.

The Flash — “Flash vs. Arrow” Pictured (L-R): Stephen Amell as Oliver Queen/The Arrow and Grant Gustin as Barry Allen/The Flash — Photo: Diyah Pera/The CW — © 2014 The CW Network, LLC. All rights reserved.

The Flash — “Flash vs. Arrow” Pictured: Jesse L. Martin as Detective Joe West — Photo: Katie Yu/The CW — © 2014 The CW Network, LLC. All rights reserved.

The Flash — “Flash vs. Arrow” Pictured (L-R): Stephen Amell as Oliver Queen and Executive Producer Andrew Kreisberg — Photo: Diyah Pera/The CW — © 2014 The CW Network, LLC. All rights reserved.

The Flash — “Flash vs. Arrow” Pictured (L-R): Behind the scenes with Director, Glen Winter — Photo: Diyah Pera/The CW — © 2014 The CW Network, LLC. All rights reserved.

Episode Description:

PART ONE OF THE EPIC CROSSOVER EVENT WITH THE FLASH AND ARROW — Barry(Grant Gustin) is thrilled when Oliver (guest star Stephen Amell), Felicity (guest star Emily Bett Rickards) and Diggle (guest star David Ramsey) come to Central City to investigate a case involving a deadly boomerang. Excited about teaming up with his friend, Barry asks Oliver if he’d like to help him stop Ray Bivolo (guest star Patrick Sabongui), the meta-human Barry is currently tracking. Bivolo causes people to lose control of their emotions and has been using that skill to robbanks. Unfortunately, the superhero partnership doesn’t go as smoothly as Barry expected. When Oliver tells Barry he still has a lot to learn, Barry sets out to prove him wrong by attempting to stopBivolo alone. However, when Bivolo infects Barry and sets him on a rage rampage, everyone is in danger, and the only one who can stop him is the Arrow. Meanwhile, Iris (Candice Patton) is furious when Eddie (Rick Cosnett) tries to get a task force to stop The Flash, Joe and Dr. Wells(Tom Cavanagh) agree the Arrow is a bad influence on Barry, and Caitlin and Cisco deal with a newteam in S.T.A.R. Labs. Glen Winter directed the episode with story by Greg Berlanti & AndrewKreisberg and teleplay by Ben Sokolowski & Brooke Eikmeier (#108). Airs December 2nd, 2014.