Prison Realm

The Prison Realm is a world featured on Once Upon a Time.

The Prison Realm is loosely similar to the pocket dimensions featured in the Dreamscape. It is also similar to the World Within the Book.

After Fifth Curse
As revenge against Regina Mills for killing his grandparents and abducting his mother, Prince Henry teams up with the Wish Realm version of Rumplestiltskin to rewrite the heroes happy ending into a tragic tale. As such, Rumplestiltskin uses the Author's pen to create various versions of the Once Upon a Time books pertaining to various individuals from all the worlds. After creating the books that works as a one way portal to the Prison Realm, Rumplestiltskin tells Prince Henry that he has to submit to the darkness in order to open the portal and uses the Wish Realm version of the Blue Fairy as an example, resulting in her banishment. Afterwards, Prince Henry and Regina duels as portals open at random to send the real Henry, the Wish Realm version of Hook, Alice, Robin, and the real Rumplestiltskin to the Prison Realm. However, Regina convinces Prince Henry to give up on revenge, resulting in the closure of the portals. ("Homecoming", "Leaving Storybrooke")

Inhabitants

 * Blue Fairy (Wish Realm)

Ways of Travelling

 * By writing into certain Once Upon a Time books, inhabitants of any world can be transported via a portal to the Prison Realm.