The promo page for Nancy Drew 31: Labyrinth of Lies is on the Internet! We have some pictures and information, as well as the fancy cover art.
It looks like the game has something to do with a museum. There is also a play about the rape of Persephone. (That's the traditional name for the myth; in this context, "rape" means "kidnapping" or "snatching", and not the modern meaning of the word.)
Frank and Joe Hardy are confirmed for this game, so...YAY!! Go Frank and Joe!