Fans of "CaptainSwan," a.k.a. Captain Hook (Colin O'Donoghue) and Emma Swan (Jennifer Morrison) were delighted by the Once Upon a Time Season 3 finale after the two shared a passionate kiss, but it won't be easy for the pair going forward.

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While Emma and Hook did share a kiss, it was clear by the end of the Season 3 finale of Once Upon a Time that Emma would be facing some bigger problems going into Season 4. Emma and Hook returned from the past successfully but they also brought one person with them: Maid Marian (Christie Laing). Bringing back Robin Hood's (Sean Maguire) love interest greatly angered Regina (Lana Parrilla), who expressed her angry feelings to Emma.

Now, going into Season 4, Emma will feel the guilt of ruining Regina's opportunity for true love in Robin Hood.

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"There will be some challenges for them," OUAT co-creator Adam Horowitz told TVLine recently, referring to Emma and Hook.

Kitsis added: "The very first obstacle is Emma's guilt over the fact that she just destroyed Regina's relationship [with Robin Hood] . . . So there's a part of her that feels guilt in starting a new romance of her own."

Morrison previously admitted that she doesn't see her character Emma being in bliss with Hook for long.

"My guess would be, since we're on a television show, that there's not gonna be bliss for very long because it's not very interesting," she admitted, noting that Emma is more vulnerable than ever before.

Once Upon a Time Season 4 premieres in fall 2014 on ABC, though the network has not yet announced a specific air date. It will be returning to its regular Sundays at 8 p.m. timeslot.

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