'Arrow' Sets Up Second Ra's al Ghul Showdown

John Barrowman - H 2015
Cate Cameron/The CW

[Warning: Spoilers ahead for Wednesdays' episode of Arrow, "Midnight City."]

Are Merlyn (John Barrowman) and Thea (Willa Holland) doomed?

Tuesday's Arrow set events in motion that could see the father and daughter face Ra's Al Ghul (Matt Nable) in a battle to the death — the very type of battle Oliver (Stephen Amell) already lost.

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Merlyn agreed to Thea's wishes to stay in Starling City and fight Ra's Al Ghul rather than flee. Merlyn is being hunted by his former allies in the League of Assassins, and the final shot of the episode revealed that Thea's budding love interest, Chase (Austin Butler), is double-crossing her by feeding information on her whereabouts to Maseo (Karl Yune) — who is in turn double crossing Oliver (Stephen Amell) as an informant for Ra's.

To add to the complications, Thea still doesn't know that earlier this season, Merlyn drugged her and tricked her into killing Sara (Caity Lotz).

"She was the pawn, and he did it to keep her safe in a very sadistic, roundabout way," Barrowman tells The Hollywood Reporter. "Does Thea find out? Does she really believe he is protecting her? Those questions provide a lot of drama." 

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In the midseason finale, Merlyn forced Thea's brother Oliver to take the blame for Sara's death, leading him his demise during a duel with Ra's. Ra's has laid low since then, but he's poised to return.

"I've got a lot to do in the back end of the season. You will see lots of Ra's," says Nable, who adds he's still learning where his character will go. "I know where it starts, and where it leads, but in between I certainly have no idea, which is exciting."

Merlyn and Thea's decision to stay could see them battle Ra's together, or potentially bring in help from team Arrow. Oliver himself could even be back in the mix by the time Ra's arrives in Starling. If that's the case, he would have plenty of reasons to be on Merlyn's side in the battle.

"Oliver will not kill Malcolm, because he has lost his dad and mom, so he doesn't want his sister to lose her father," Barrowman says. "It creates a whole new relationship between the three of them."

Email: Aaron.Couch@THR.com
Twitter: @AaronCouch