While Arrow's farewell season doesn't officially kick off for another month, the writers have already begun working on the final episode of the series -- and the reality that the end is near is starting to hit home.

"In the [writers'] room [Monday], we started working on the series finale so it felt very real," showrunner Beth Schwartz confessed to ET, which exclusively debuts a new photo featuring members of the original Arrow cast, Oliver (Stephen Amell), Diggle (David Ramsey) and Laurel (Katie Cassidy Rodgers), all suited up and ready for battle. "I couldn't believe it. Just saying it, it felt a little bit surreal. Towards the end of every season, we start breaking what's happening next season and this year, there isn't a next season. It feels very strange."

Unlike previous seasons, the CW superhero drama only has 10 episodes to wrap up its eight-year run and Schwartz shared that she and the other producers are treating these final 10 episodes like a "greatest hits" album. Though they've "always had a plan for the series finale," Schwartz revealed that the plan for the series' swan song has evolved since this season started.

"Now that it's here, we're obviously going to add more things that did evolve from this season specifically," she said, adding that she and fellow executive producer Marc Guggenheim haven't shifted on "where we wanted to end it."

On Tuesday, The CW released the first official photos from the season eight premiere, titled "Starling City," featuring Arrow fan favorites Moira Queen (Susanna Thompson), Oliver's late mother, and Tommy Merlyn (Colin Donnell), Oliver's late childhood best friend, in the once familiar Queen mansion. 

"This season is definitely a reflection of all the previous seasons," Schwartz said. "The premiere is very nostalgic of the pilot and of season one, visiting those sets, like Queen mansion, that we all love and we all have [people] we've tried to bring back a few times -- those characters that were really there from the very beginning and helped to create this series and what made it so successful."

Crafting those pivotal final scenes with characters like Moira and Tommy didn't prove challenging for the writers, Schwartz promised. Instead, they provided new opportunities to give these key characters -- many of whom died valiant deaths over the course of the series -- proper goodbyes.

Other familiar faces popping in for one last go include Adrian Chase (Josh Segarra), Malcolm Merlyn (John Barrowman), Tatsu Yamashiro (Rila Fukushima) and Yao Fei Gulong (Byron Mann). 

"It felt nostalgic and kind of perfect for the end of the series to have these final scenes with these characters we haven't seen in a while. It felt right that this is how we should end the season and it was fun to write for Moira again and to write for Tommy and all the characters we wrote for eight years ago," she said. "It felt natural."

A lot has been made of the upcoming eighth season, which will abandon the show's signature flashback/flash-forward format and approach each episode as its own event, leading up to the massive Crisis of Infinite Earths crossover, airing across five DC shows (with a special appearance by the Black Lightning cast) in December and January. 

Schwartz revealed that there is one other thing that will be different this season on Arrow: There will be a new introduction voiced by Amell for the show's final run. "Yes, we will have a new one this season," she said. "We had a new one last season and there will be a new one this year as well. It's the last one."

Production is past the midway point on the final season, a fact Schwartz still hasn't quite wrapped her head around.

"It definitely feels like this is the right time for the series to end, but I feel like it's not going to feel quite real until that last script of the finale comes out. And then I feel like there's going to be a lot of tears," she admitted. "I'm sure it'll be the same thing on the last day of filming on set. That's when it's going to feel even more real when we're actually going through it."

Arrow kicks off its final season Tuesday, Oct. 15 at 8 p.m. ET/PT on The CW.

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