The Flash: Grant Gustin, Stephen Amell and Director Danielle Panabaker Tee Up 'Ambitious' Reunion Episode

Grant Gustin was as surprised as anyone to learn that Stephen Amell would reprise his role as Arrow‘s (dearly departed) Oliver Queen in one of The Flash‘s final episodes ever.

“I didn’t think it was on the table, honestly,” Gustin shares with TVLine in the video above. In fact, “I didn’t know what to expect” from The Flash‘s last run of episodes, he adds, laser-focused as he typically is on the script at hand.

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Titled “It’s My Party and I’ll Die If I Want To” and directed by original cast member Danielle Panabaker, the Wednesday, April 26 episode of The Flash opens with a surprise birthday bash for Barry, who is turning 30… again. (The gamma radiation Barry absorbed late in Season 8, it is explained, de-aged the speedster some.)

Alas, Dr. Ramsey Rosso aka Bloodwork (returning guest star Sendhil Ramamurthy) proves to be quite the party crasher, having escaped ARGUS to catapult Barry, Iris, John Diggle (Arrowverse vet David Ramsey), Wally West (Flash and Legends of Tomorrow vet Keiynan Lonsdale) et al into a nightmare scenario. As Barry labors to navigate the perilous situation, “A hero returns,” the trailer tells us, in the form of of Amell’s character.

With that encore, The Flash closes a full circle started with Arrow Season 2’s “The Scientist,” in which Gustin made his TV debut as someday-speedster Barry Allen.

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