SPOILER WARNING: This article contains major spoilers for “Inmate 4587,” the Arrow Season 7 premiere.

Actor Ben Lewis has been cast as the adult version of Oliver Queen's son William for the flash forward sequences of Arrow Season 7. He made his first appearance in "Inmate 4587," the season premiere.

"Thanks, dad! Humbled and proud to be your (TV) son," Lewis told Arrow star Stephen Amell in over Twitter. "Especially after watching that premiere!"

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In the episode "Inmate 4587," this older version of William can be seen venturing to Lian Yu, where he encounters an aged Roy Harper/Arsenal. William proves his identity to a skeptical Roy by producing the carved arrowhead that was given to him as a child earlier in the episode.

“Now with the flash-forwards, you’re able to see what is happening in the present day, [and] how that affects the characters in the future,” showrunner Beth Schwartz said in an interview with TVLine.

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This is not the first time Lewis played a comic book character. He previously appeared in the fan-favorite 2010 film Scott Pilgrim vs. the World as the character Other Scott, the boyfriend of Scott Pilgrim's roommate Wallace. Prior to joining the cast of Arrow, Lewis has also appeared in such television shows as Chasing Life, Suits and Degrassi: The Next Generation.

Airing Mondays at 8 pm ET/PT on The CW, Arrow stars Stephen Amell as Oliver Queen, David Ramsey as John Diggle, Emily Bett Rickards as Felicity Smoak, Rick Gonzalez as Wild Dog, Echo Kellum as Mr. Terrific, Juliana Harkavy as Black Canary and Katie Cassidy as Black Siren.