Arrow is a show big on consequences, so it shouldn't come as a surprise that when the series finally shows us the Lazarus Pit (something that's been hinted at throughout show), someone is going to pay the price for using it.

Please note that the following contains spoilers for tonight's episode of Arrow.

Last week's episode of Arrow ended on a very low note: Ra's Al Ghul breaks into Thea's apartment and stabs her, presumably to death. Now, let's face it, the show's writers aren't stupid enough to kill off another female character, especially one that's just finally finding her path and getting interesting.

Enter the Lazarus Pit. In a sneak peek of this week's episode, we see Thea not only being lowered into the pit, but also arising from it.

However, those familiar with the Lazarus Pit as a plot device in the comics know that it unleashes the dark side of whoever goes into it. Take a look at the preview below: 

So what will happen to Thea? Will she become evil Thea? Arrow executive producer Marc Guggenheim provided a hint to The Hollywood Reporter.

"Everything in the show has consequences, and that's something we've been consistent about," says Guggenheim. "It's something you will continue to see not just through the end of season three, but into season four..."

So exactly what does that mean? Will the consequences entail Oliver finally agreeing to become the new Ra's al Ghul? Obviously, he's had to make a deal with the current Ra's, who has allowed him to save Thea in the Pit.

In the following clip, Malcolm Merlyn tells the team about what Felicity refers to as "the magic hot tub."

"The waters change a person, in the soul," says Merlyn. "Even if they work, the Thea you get back will not be the one you lost."

In other words, it's likely that we'll be seeing an evil Thea soon. We'll admit we're kind of excited about action scenes pitting Thea against Oliver in the near future.

So where does that teased Oliver and Felicity make out scene put in an appearance? We're guessing it happens right before he leaves for Nanda Parbat to drop his sister in the Pit, while he becomes the new head of the League of Assassins.

[Photo Credit: The CW]

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