Mary Margaret apologizes to Regina for murdering Cora in this Once Upon a Time scene. Watch as the frenemies then hear a strange noise.
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Once Upon a Time Season 3 Episode 18 Quotes

Right now I need something to defeat the woman who's puppet mastering your boyfriend.

Regina

Zelena: Red apples are so sickly sweet don't you think. People tend to like something sharper.
Regina: And green apples are just bitter.