Every night, when the rest of the castle has gone to bed, The 12 Princess descend a hidden staircase to an enchanted kingdom, where they dance through the night and right through their shoes.

I found the pictures too dark in this paperback version.

When twelve princesses are locked in their room every night, nobody expects them to have worn out shoes in the morning, least of all their father, the King. This mystery continues until the King appeals to princes and brave men in the realm to find out the mystery of the worn out shoes. Prince after prince fails to discover the mystery and win the hand of one of the princesses in marriage until a simple soldier, wiser with the help of an old woman tricks the princesses into revealing their secret. ( )