The Flash showrunner teases series finale full of 'greatest performances ever'

The Flash is entering its final run.

Ahead of the penultimate episode, EW has your exclusive first look at the series finale of the CW's last remaining Arrowverse series, which showrunner Eric Wallace describes as "bittersweet."

"I'm very proud of the whole season, but boy, I can't wait for the fans to see these last episodes," the showrunner told EW prior to the writers' strike. "I can't wait to unleash them on the world. We have some people that have been with the show since day one, and they gave their greatest performances ever."

Colin Bentley/The CW Grant Gustin as Barry Allen/The Flash

The second half of the epic four-part series finale continues Wednesday with "A New World: Part Three," featuring the returns of Rick Cosnett as Eddie Thawne and Jessica Parker Kennedy as Nora West-Allen. Team Flash works together to figure out how to protect Barry (Grant Gustin), all while being very careful who they trust. And it's all leading to the series finale on Wednesday, May 24, "A New World: Part Four," as the Flash is tasked with his greatest challenge yet: To save the timeline and save existence. Friends old and new gather for an epic battle to save Central City one last time.

"It's just a labor of love all around," Wallace says of the conclusion to the four-part saga. "The crew, cast, writers, directors, everybody, it's the hardest we've ever worked. Not that we haven't had even bigger episodes because certainly a crossover is bigger, but the commitment to excellence that everybody was bringing with knowing that these were the last batch of Flash episodes was unmatched. We were a family. I'm going to miss my Flash family."

Check out the series finale poster featuring Gustin unmasked below:

The CW 'The Flash' series finale poster

The Flash airs Wednesdays at 8 p.m. ET/PT on the CW.

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