More on the Twelve Dancing Princesses

The Twelve Dancing Princesses is a fairy tale.  Like many fairy tales, there are different versions, but I based this episode on the one collected by the Grimm Brothers.  That version is in the public domain, and you can read it for yourself here. 

Here's how it goes:

A king has twelve daughters, who lately have been sleeping well into the afternoon and turning up with their shoes worn to pieces.  Even when he locks them all in their communal bedroom, they still seem to be getting out to go dancing.  He really wants to know where they go, but apparently doesn't ask the daughters, or maybe he does and they refuse to tell him and the Grimm Brothers didn't find it necessary to put it into the story.  The king offers a reward that if anyone can figure out where the princesses go, they can marry one of the daughters.  But if the suitor doesn't figure it out within three days, he'll be beheaded.  So a bunch of guys try, and they all get beheaded one after another.  One day, there's an old soldier walking through the woods when he comes upon a woman who's obviously a witch.  She says, "Where are you going?" and he says, "I was going to go try to figure out where the princesses are going."  And she says, "Well, take this cloak of invisibility.  And also don't eat or drink anything the princesses offer you.  Good luck!"  When he gets to the castle, and announces he wants to figure out where the princesses go, the oldest princess offers him some wine.  He thanks her and pretends to drink it.  Then he pretends to pass out.  Pleased with themselves, as soon as they're locked in their room the princesses open up a secret passageway behind the oldest sister's bed. 

I guess the old soldier was staying in their room, and that's how he saw this and was able to follow them into the tunnel even though they were in a locked room.  I also guess this is why all the guys were beheaded: because they'd all spent three nights in the princesses' bedroom?  It's unclear.

So the soldier puts on his invisibility cloak and follows them.  First they go through a cave of silver tress, then a cave of gold trees, then a cave of diamond trees.  The whole way, the youngest princess thinks she hears someone following them, but the oldest princess tells her she's being paranoid, and they keep walking.  They get to a magical lake where a fleet of boats comes up, each boat piloted by a prince.  The princes take the princesses to a magical castle where they dance all night until their shoes get worn out.  The old soldier snaps off some branches from the magic trees and then steals a golden goblet from the party, and when he announces to the king where the princesses are going at night, he presents these as proof.  The king asks which princess he wants to marry, and he says the oldest, because he's pretty old himself.

I guess he didn't mind that she'd tried to drug him.  I guess it doesn't matter whether or not she has any thoughts on this situation.

I also guess the king was able to do something to stop these nighttime excursions to a magical dance castle, but that's not part of the story.  Or maybe the dad didn't care about the shoes, he just wanted to know what they were up to, and now that he knows the eleven remaining princesses can carry on.  Do the princesses go back to the magic castle minus one sister?  Are they barred from re-entry after being discovered?  If so, do they miss it?  Did their father deny them their only means of escape?  And why did they need an escape in the first place?