The star says the ramifications of Oliver's duel with Ra's Al Ghul continue well into next season.

[Warning: Spoilers ahead for Wednesday's episode of Arrow, "Uprising"]

Oliver Queen (Stephen Amell) made a dramatic return from the dead in Wednesday's Arrow.

Oliver made his way back from oversees, and delivered a dramatic speech after convincing Merlyn (John Barrowman) to spare Brick's (Vinnie Jones) life, even though the gangster was responsible for the death of Merlyn's wife.

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"You did not fail this city, and I promise I will not fail you," Oliver said to the crowd.

Amell says Oliver returns to Starling City a changed man after losing a duel to the death with Ra's Al Ghul (Matt Nable) and only being saved thanks to the healing powers of Maseo (Karl Yune) and Tatsu (Rila Fukushima). He'll now team up with Merlyn in the coming rematch against Ra's.

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"He comes back having been humbled, which is an important lesson for anybody," Amell tells The Hollywood Reporter. "You constantly have to be on the lookout for people in the world that are just going to destroy you."

Taking on Ra's was a foolhardy move ("It was not even that close," says Amell of the duel), with Oliver going headstrong into the battle because otherwise his sister Thea (Willa Holland) would have been faced the same fate, as she murdered Sara (Caity Lotz), though only after being drugged by her father Merlyn.

Arrow has been a show about a man's journey from vigilante to hero. In season one, Oliver was a killer. In season two, he took a vow not to kill, going as far as to spare Slade (Manu Bennet), the man who killed his mother Moira (Susanna Thompson). His apparent death in season three is one step more on that journey to hero, says Amell.

"This will make perfect sense when you see season four, but the Arrow persona, the vigilante, the hood — that's a flawed persona," he says. "We saw it be flawed. We saw him lose. There has to be something more. We'll see that eventually."

Arrow airs Wednesdays at 8 p.m. on The CW.

Check out the trailer for next week's episode:

Email: Aaron.Couch@THR.com

Twitter: @AaronCouch