With Arrow coming back for Season 3 this fall and spin-off series The Flash debuting as well, the possibilities for crossover episodes are practically endless. When Barry Allen (Grant Gustin) debuted in two Season 2 episodes of Arrow, fans saw the start of a potential romance between Barry and Felicity Smoak (Emily Bett Rickards), but can a relationship last between two different shows, set in two different fictional cities?

Greg Berlanti, who serves as executive producer on both Arrow and The Flash, was asked if Felicity will ever pop up on The Flash, revealing he hopes to start crossovers between both shows as soon as possible.

"That's our hope. Our hope is to get some crossovers going sooner rather than later with all the shows."

He added that the producers toyed with Felicity and Barry dating between both of the shows, similar to the crossover relationship between Kelly Severide (Taylor Kinney) on NBC's Chicago Fire and Erin Lindsay (Sophia Bush) on the spin-off Chicago P.D. While he wouldn't say exactly how they plan on pulling it off, Greg Berlanti teased there are many different possibilities on both shows.

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"We have all sorts of romantic possibilities for both of them on both shows. Hopefully the first time Felicity comes to town, we'll deal with all that stuff."

In related news, Caity Lotz is set to return as Sara Lance/Black Canary in the Season 3 premiere of Arrow. At the end of Season 2, Sara handed her leather jacket to her sister Laurel (Katie Cassidy) and disappeared with Nyssa al Ghul (Katrina Law). It isn't known if Caity Lotz will be back for just the premiere, or if she will be sticking around Starling City for more episodes.

We reported last month that The Flash debuts on Tuesday, October 7 at 8 PM ET, with Arrow's Season 3 premiere coming just one day later on Wednesday, October 8 at 8 PM ET on The CW.