In advance of filming on The Flash Season 9, which will be the final entry in the popular The CW show, star Grant Gustin shared a heartfelt message about the series with fans.

On Instagram, Gustin shared a post, which you can read below, saying that filming on The Flash Season 9 was starting soon. In the caption, he wrote, "I'll save the long, emotional captions for later in the season, but to say I'm grateful for this journey and the growth it's provided me in so many different ways would be a gross understatement. Thankful to everyone who helped give me this opportunity and all the fans of the show that have showed me and anyone that’s been a part of The Flash love along the way." Gustin then shared several photos and a video from his first year on the show.

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What's The Flash's Run Been?

Based on the DC Comics character of the same name, Gustin's iteration of Barry Allen/The Flash first appeared in an episode of Arrow, from which the Arrowverse derived its name. The character's solo series premiered in 2014 and has since run for eight seasons. The Flash follows Allen, who gains powers after the explosion of a particle accelerator at S.T.A.R. Labs, as he and his allies fight against such dangerous metahumans as Eobard Thawne/Reverse-Flash, Clifford DeVoe/The Thinker and Eva McCulloch/Mirror Monarch.

Due to Arrow having ended in Season 8, The Flash is the longest-running of The CW's Arrowverse shows. Several other Arrowverse shows have been canceled in the last year, including Legends of Tomorrow and Batwoman. While Superman & Lois does use characters from the main Arrowverse, the show's most recent season made clear that it was set in a different continuity.

RELATED: The Greatest Gift the Flash Gave Fans Was the Original Barry Allen

Allen was created by Robert Kanigher and Carmine Infantino, with the character first appearing in 1956's Showcase #4. The speedster is technically the second person to hold the mantle of The Flash, with the original being Jay Garrick. Despite a long absence from the comics following the events of Crisis on Infinite Earths, Allen has been a mainstay of the DC Universe and served on such important teams as the Justice League.

The Flash Season 9 is expected to premiere in early 2023 on The CW.

Source: Instagram