A tectonic shift is in store for Arrow.



As we approach the final four episodes of the season, things are about to look drastically different – yet again – for Oliver and Starling City. Now that Ra’s al Ghul has put Thea on the clock, the leader of the League of Assassins is about to get what he wants: Oliver. To save his dying sister, Oliver travels to Nanda Parbat to bring her back to life via the magical waters of the Lazarus Pit. In exchange, he must give up everything to join the League.

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ETonline was one of the lucky few to catch an early screening of this week’s Arrow, titled “The Fallen,” and we highlighted a few things you should know, including that Oliver and Felicity moment.

1. Oliver and Felicity's sexy hook-up

This week’s Arrow is significant for many reasons, one of which includes a big step forward for Oliver and Felicity’s romantic future, as you may have already seen in the trailers. “I think it’s the next step in their relationship,” executive producer Andrew Kreisberg told ETonline. “We root for characters to be together as much as anybody. You’re sort of the ultimate shippers when you’re creators of the show. I think the time has come for them – they’ve been dancing around it for a long time – to really declare how they feel for each other.”

Even so, their conversation leading up to that moment, who pushes them together and what takes place in the immediate aftermath is both surprising and heartbreaking considering their circumstance. Kreisberg offered these questions to consider: “What happens after that? Where does that take them?" If you've also been wondering why Felicity hasn't uttered those three magical words to Oliver yet, there's a very good reason.

2. Roy Harper’s return ties up loose ends



Team Arrow’s goodbye to Roy (and Arsenal) in last week’s episode had us shedding a few tears but thankfully, Oliver’s former sidekick will be back in the May 6 episode, “This Is Your Sword,” to wrap up some unfinished business.

“The thing we felt we owed the audience more than anything was some closure with Thea because [of] the circumstances under which Thea is in,” executive producer Marc Guggenheim said of Wednesday’s installment. “Certainly we owed the audience some closure for this three season-long love story between these two characters.”

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3. Team Arrow has a new HQ



Thanks to the police raid (R.I.P. fern), Team Arrow’s lair as we know it is gone – “kiboshed,” as Guggenheim puts it. Forced to find another location to congregate and plan, they turn to a familiar place to call Arrow HQ for the rest of the season: Palmer Technologies, formerly Queen Consolidated.

“We had to expand Ray’s workshop to allow scenes with a huge group of people rather than just Ray and Felicity,” Guggenheim said, adding that they did “set redesign and set redecoration” to make it work. That being said, he revealed that the old lair will get an encore appearance in the April 29 episode, titled “Al-Sahim.”

4. Starling City’s perception of the Arrow’s fate is a question



The identity of the man under the hood is no longer a secret to Starling City, even if the public believes that the Arrow is now presumed dead. How the city perceives the Arrow’s fate and masked heroes as a result of this revelation remains a looming question, one that Guggenheim said they have struggled with.

“We don’t have a newspaper reporter who you go home with, who you learn about everyone’s opinions,” he said. “I would love to develop that aspect of the show. We just haven’t figured out how to do that yet because it’s just not where the show lives at the moment.”

5. The mystery behind the finale



Arrow Season Finale “mystery” set completed: pic.twitter.com/BF603fftG5 — Marc Guggenheim (@mguggenheim) April 15, 2015

Last week Guggenheim posted a photo of a brand-new set featuring what looked like a cargo plane and he offered some hints about how it factors in during the finale, titled "My Name Is Oliver Queen."

“Right now there are no plans for it to play beyond [the finale],” he hinted. “There’s a fair amount of green-screen work to make it work, and the scene that we shot featured Ra’s, Nyssa and Oliver.” Any guesses on what the scene could be?



We’ll be back here on Wednesday for all the scoop on the big events from the latest Arrow, and believe us, you don't want to miss this one!What are you most looking forward to? Tweet Philiana Ng at @insidethetube on Twitter and share your thoughts!



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

Press play on the video below to hear what the Arrow stars have to say about Oliver Queen as the next Ra's al Ghul!