We saw in Episode 11 (Fruit of the Poisonous Tree), Emma uncovered a set of mysterious keys in Regina’s office. Check this previous blog post about it – http://www.onceuponatimepodcast.com/ouat-what-do-these-strange-keys-from-reginas-office-unlock/
We also learned that it’s possible that one of those keys opens the Snake Box.
In Episode 13 (What Happened to Frederick), we see Regina using one of the keys to enter into David and Kathryn’s house. Check this previous blog post about it – http://www.onceuponatimepodcast.com/ouat-so-we-see-other-things-skeleton-keys-open/
In this episode (Heart of Darkness), we see Henry has stolen the keys from Regina’s office and confirmed to Emma (and the viewers) that these keys can open any door in Storybrooke.
Henry forces Emma to try the keys to see if it works. After a couple unsuccessful attempts, a key with an apple insignia finally opens the door. Apple refering to Snow White/Mary Margaret.
Towards the end of the episode, Mary Margaret finds a key under her bed in the jail cell. The key had a skull insignia. Maybe referring to a dungeon?
Does each key in the set have an insignia that pertains to different characters in Storybrook? What could Mr. Gold, Granny, Red or Jiminy’s key symbols be?
Share with us your thoughts in the comments below.
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