There will be multiple interesting developments between Snow/Mary Margaret (Ginnifer Goodwin) and Charming/David (Josh Dallas) on upcoming episodes of Once Upon a Time.

ABC recently released a synopsis for the next episode of Once Upon a Time, titled Dark Hollow. The episode will feature Mary Margaret being very upset with David after he didn't tell her about his poisoning incident. Dallas recently spoke with TV Guide about what to expect from the fairytale couple in the future.

"We're going to open up right after they get married," Dallas teased. "Snow wants to get back at Regina for destroying her wedding basically. Charming just wants to go on the honeymoon. He just thinks it's a threat coming from Regina, that's all it is at the moment."

It is not yet clear if Dallas' comments refer to the upcoming episode or something in the future, but viewers should expect some developments from Snow and Charming, both in the past and the present.

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Episode 7 promises to be an eventful one, according to the synopsis. The episode will involve Mr. Gold (Robert Carlyle) and Regina (Lana Parrilla) sending Ariel (JoAnna Garcia Swisher) to Storybrooke with something that will help Belle (Emilie de Ravin) find a hidden artifact. This artifact will allow the gang to help take down Peter Pan (Robbie Kay).

However, this will be easier said than done as two men have broken into Storybrooke to try and stop the entire mission from happening. Back in Neverland, Emma (Jennifer Morrison), Neal (Michael Raymond-James) and Hook (Colin O'Donoghue) will try to find the Dark Hollow, which is the location of Pan's shadow.

Marilyn Manson to Voice The Shadow on Once Upon a Time 

Once Upon a Time airs Sundays at 8 p.m. on ABC.

Watch a preview for episode 7 here:

Tags: Once Upon A Time Once Upon A Time Season 3 Spoilers