Hall of Infinite Doors

You untie the girl and she runs away without a word. How ungrateful! She'll taste your fury the next time you run into her. In your anger you punch a previously unseen squirrel off of a nearby low-hanging branch. Startled it runs up the tree, apparently tickling it because it jiggles a little and you hear some more of its laughing. In fact, it is such a ticklish tree that a few of its fruits fall off at your feet.

You gladly pick up the fruit, begin to eat it and walk away. You're a good distance away before you hear a group of voices from where you just were. "Damn it!" they explain, "Our captured genie has escaped! She's the only one who can lead us to the Stair Tree!"

You couldn't have heard right. That girl was a genie? And what's a stair tree.