Oliver Queen will team up with Barry Allen one last time in the ninth and final season of The Flash. The CW announced today that Stephen Amell who starred as the character in both Arrow and Arrow spinoff The Flash will return to guest star in episode 909, joining previously announced David Ramsey (John Diggle aka Spartan), Keiynan Lonsdale (Wally West/Kid Flash) and Sendhil Ramamurthy (Ramsey Rosso/Bloodwork).
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