"Once Upon A Time" season 4 spoilers hint of rough sails for the relationship between Emma and Captain Hook, as her past might finally catch up to her.

According to showrunner Adam Horowitz, who revealed "Once Upon A Time" season 4 spoilers to TV Guide, Emma and Captain Hook will have a tough time making their relationship work.

"Just because we saw their feelings reach a new level at the end of last season doesn't mean that that's the end of the story. Emma is obviously a person who has a tough time trusting people and letting her guard down," he said. "Sometimes you may feel something for somebody but your feelings hold you back."

Producer Edward Kitsis earlier said that Emma Swan and Captain Hook will finally go on an official date this season. Because even if they had their romantic moments in the past, they never had a proer date.

In a Digital Spy video interview earlier this year, Jennifer Morrison, who plays the bounty hunter Emma Swan, dished out "Once Upon A Time" season 4 spoilers as she claimed that her character's romance with Captain Hook might not last a long time.

"My guess is that since we're on a television show, the bliss is not going to be for long because that's not very interesting. Nobody wants to watch a show of a bunch of happy people," she said, adding that she really doesn't know the obstacle that will hinder them from having a happy ending.

In another interview with Entertainment Weekly, per Yahoo News, Adam Horowitz teased more "Once Upon A Time" season 4 spoilers when he said that they will explore Emma's past more than ever in future episodes.

"In the first half of the season, we're going to see more of Emma's past than I think we've seen in all the other previous seasons combined," he said.

Emma has had her fair share of flashbacks over the course of "Once Upon a Time," but will her flashbacks have Neal (Michael Raymond-James) in them?