Arrow Postmortem: What Are Slade's Plans for Thea?

[Warning: This story contains major spoilers from Wednesday's episode of Arrow. Read at your own risk! ]

Slade Wilson has taken the first shot in the war against his former friend.

The closing moments of Wednesday's episode of Arrow likely made fans scream at their television screens a la the dumb blonde running from the killer by going upstairs. Upset that Roy (Colton Haynes) cheated on her, Thea (Willa Holland) decided to walk home from Verdant. Alone. This, of course, provided Slade Wilson (Manu Bennett) with the perfect opportunity to roll up in his car and ask if she needed a ride home. Suffice it to say, Thea is not safe now that she's in the clutches of Oliver's (Stephen Amell) greatest enemy.

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"The Sword of Damocles that's being held over her is a double edge sword — it's both physical and emotional," executive producer Marc Guggenheim says. "I can guarantee that by the end of Episode 18, one of those edges is going to cut her."

Fittingly titled "Deathstroke" for Slade's alter ego, next week's episode will serve as one of the most epic, heart-stopping hours of the season as the show delves into what really makes Slade tick after being injected with the Mirakuru serum. "He's clearly not in his right mind," Guggenheim says. "Episode 18 will give you a lot of insights into what's going on in his head. We really do get a much greater sense of Slade's agenda, where he's coming from, but also what's going on in his head."

It's that very reason that Thea's life is in great danger. After all, Slade has promised to destroy everything Oliver holds dear. Slade would consider killing Thea too easy and would prefer her to suffer first — and she will suffer. "Thea learns something pretty massive in Episode 18, and it will cause a tectonic shift in her relationship with Oliver," Guggenheim says. That could mean finding out about Oliver's extracurricular activities or, worse, the truth that she's Malcolm Merlyn's (John Barrowman) daughter. "The secret that Moira [Susanna Thompson] and now Oliver have been keeping from Thea will cast a very long shadow over the rest of the season," Guggenheim says. "That will play a pretty big role all the way up to the finale."

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Unfortunately, Thea's kidnapping comes after she discovered Roy kissing another woman, which was a ruse to get Thea to break up with him because Oliver asked Roy to stay away from his sister. "If we were going to play Thea in jeopardy, we wanted Roy to feel some sense of complicity in that," Guggenheim says. "Roy [is] dealing with his own sense of responsibility. 'If I had not broken up with Thea, she might not be in Slade's clutches right now.' How does Roy deal with that?"

Likely he won't deal with it well, especially since Thea was the one thing keeping him in check. So much so, Oliver invoked her nickname Speedy — a nice nod to Roy's comic book alter ego — to prevent him from killing a decoy thug. "The reason we did it was we want to keep inching Roy towards an Arsenal place," Guggenheim reveals, referring to one of Roy's possible alter egos he would evolve into after being Oliver's sidekick. "One of the running gags is that he keeps getting called Speedy, 'I don't like that nickname. Come up with another nickname for me.' When the time is right, eventually the nickname that will stick will be Arsenal."

Are you looking forward to the Oliver vs. Slade showdown? Excited to see Arsenal? Hit the comments!

Arrow airs Wednesdays at 8/7c on The CW.

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