The finale episode of "Once Upon A Time" Season 4 saw the transformation of Emma Swan (Jennifer Morrison) into the "Dark One," otherwise known as the "Dark Swan," when she put her life on the line in an effort to give Regina Mills (Lana Parilla) the happy ending the latter so earnestly fought for. With that decision, however, Emma not only put her life in peril but also the lives of the people close to her. As fans and followers of "Once Upon Time" would know, Snow White (Ginnifer Goodwin) and Prince Charming's (Josh Dallas) daughter is in the midst of a romance with none other than Captain Hook (Colin O'Donoghue). Hence, it would be quite interesting to see how the love story of the two will play out especially with Emma's dark transformation.

"It's really difficult for Hook, because he spends most of the last season trying to protect her from the darkness, because he understands what that means," O'Donoghue explains via Pop Sugar, referring to the by which his character will come into terms with Emma becoming the Dark Swan. He adds "Certainly he's trying to protect her heart."

While O'Donoghue admits that Hook might actually appreciate Emma's new wardrobe as the Dark Swan - going as far as teasing that he will "probably even borrow her pants," the actor believes that his characters is "fully invested" in their romance. "I think he'll do whatever it takes to try to bring the woman loves," he shares. The actor then goes on to compare Emma and Hook's love story to that of Rumplestiltskin (Robert Carlyle) and Belle French (Emilie de Ravin). He says, "It's the same way that Belle loves Rumpel, even for the darkness that's in him. It's going to be interesting with Hook figuring out a way to bring Emma back and whether or not he can do that - or whether or not he'll decide to go back to the darkness. That's where his struggles are going to be, I think."

Meanwhile, Dallas believes that the transformation of Emma will surely affect his relationship with Goodwin's character. "It is definitely going to put a strain on Snow and Charming's relationship," Josh Dallas shares, according to Entertainment Weekly. He adds, "There are things they're going to go through in finding their way back to Emma." Dallas is quick to point out though that the entire season will not be filled with negative consequences and events. He says, "But it's not all doom and gloom this season." Dallas goes on to say, "You're going to see Charming have a big bromance with King Arthur and go on some adventures." He also shares that the upcoming season will feature Snow White's Prince Charming at his finest. Dallas discloses, "We're going to see Charming at his most heroic in Camelot."

"Once Upon A Time" Season 5 will premiere on September 27, 2015.