When "Arrow" returns at the end of the month, the show will take a deep dive into Oliver and Felicity's romance (or lack thereof). Speaking to TVLine, executive producer Marc Guggenheim revealed that an upcoming Season 5 episode will explore their relationship -- as well as the way it ended -- in depth.

“One of the things that we’ve always wanted to do, and I think a lot of the fans have asked for, is basically deal with the consequences of [season] 4 [episode] 15 [when] Oliver and Felicity ended their engagement and broke up,” explained Guggenheim. “They never really had a full-on discussion or exploration of why that breakup happened. Felicity just sort of reached her breaking point and walked out the door.”

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“It comes out of the events of [season] 5 [episode] 19 and, quite frankly, all the other episodes that led up to it," he added.

Oliver and Felicity's relationship -- called "Olicity" by fans of the pairing -- infamously went down in flames in Season 4. Shortly after a shootout that left her paralyzed, Felicity discovered Oliver had a secret son that he had known about for some time and never told her about. She wheeled into their apartment to discover him leaving a message for his son, explaining why he couldn't be part of his life, and she decided to end their relationship then and there. Immediately afterward, she stood up and walked out of the room thanks to technology developed by Palmer Tech. Though things were certainly awkward between them for a while, they quickly set their differences aside for the sake of the team, and they were ultimately able to bring Damien Darhk down together.

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Now, this season will explore their breakup in full. Titled "Underneath, Season 5 episode 20 will be a bottle episode, which means no other characters but Oliver and Felicity will appear in it. Star Stephen Amell teased the episode with a Tweet that read “First episode EVER where the same actor shares every single one of my scenes with me. Going to be great.” He didn't clarify who he would be sharing scenes with, but the report confirms that he was talking about Emily Bett Rickards, who plays Felicity.

Starring Stephen Amell as the Emerald Archer, “Arrow” airs Wednesdays at 8 pm ET/PT on The CW. The series also stars Emily Bett Rickards, David Ramsey, John Barrowman, Willa Holland and more.