Although Oliver Queen and Felicity drove off together into the sunset at the end of "Arrow's" Season 3, new spoilers reveal that the new couple will face the same type of relationship challenges that most couples endure when the show returns this fall.

In the Season 3 finale, Oliver decided to hang up his hood and leave Starling City in order to start a new life with his girlfriend, Felicity. However, Oliver's newfound peace and happiness will be interrupted in the Season 4 premiere when he is called back to Starling City to face off with a villain of "pure evil" named Damien Darhk. Meanwhile, the executive producer said that Oliver and Felicity will face other obstacles in their relationship.

"We really wanted to explore the ups and downs of a traditional TV relationship, like we've established with Oliver and Felicity, and pretty much throw everything at it that we can and see if they'll make it through," executive producer Wendy Mericle told TV Guide.

Mericle also teased that Felicity will bond with Curtis Holt, a fellow tech-genius and the future Mister Terrific, in the new season.

"He's going to fill the void that Ray left, not as a romantic interest for Felicity, but as someone who is an equal intellectually to her and that we can have fun scenes between her and Curtis Holt in Palmer Tech," said Mericle.

According to Mic, actor Echo Kellum will play Curtis Holt, who will be the first openly gay black superhero to fight with Team Arrow.

"We're often asked when we're going to add another LGBT character to the show and our version of Mr. Terrific happens to be gay for anyone that cares about that kind of stuff," executive producer Marc Guggenheim said.

In addition to Curtis Holt, Sara Lance, aka Canary, is the show's other LGBT representative. Actress Caity Lotz plays the openly bisexual character.

Series co-creator Greg Berlanti, who is also openly gay, told the Advocate that the show is making an effort to be more inclusive towards the LGBT community.

"The network has been very welcoming and they realize the younger generation doesn't really have issues with that kind of stuff," he says. "They don't really see [being LGBT] as a negative. There's a lot more understanding, openness and compassion around this issue today and that's a great thing."

Actor John Barrowman also opened up about Sara Lance and his character, Malcolm Merlyn, during an interview with BuddyTV. According to him, fans can expect to see Sara, who suffered from a shocking death early on in Season 3.

"We know she is alive [and] will be back," he teased. "How she's brought back to life that will be the interesting part." He added that he "would like to think that Malcolm has a little bit of a hand in on bringing her back."

Barrowman went on to joke that now that Malcolm is the leader of the League of Assassins, "the League will have casual Fridays."

Furthermore, he said that Malcolm will be a "proud" and protective dad when his daughter, Thea, transitions into the superhero Speedy.

Watch his interview below.