Universe (The Oubliette)

Jenny Everywhere and her companion Laura were once thrown into an “inescapable prison” known as the Oubliette in one universe. To get out, Jenny, unable to simply shift, (PROSE: The Oubliette) telepathically communicated across time with her counterpart in this world, who lived around the time when the complex containing the Oubliette was built. She then bribed the architect to build a secret escape route, which would only open if Jenny made an elaborate gesture with her hands in front of the right wall while humming a particular tune. (PROSE: The Oubliette: Solution)