Waterdeep:Vault of Dragons

When Dagult Neverember embezzled 500,000 gold dragons from Waterdeep, he needed a place to store it. He used an ancient dwarven ceremonial vault he had discovered underneath the crypts of his late wife's family. Then he paid Aurinax to guard the treasure. Then he used the Stone of Golorr to erase all knowledge of the location of the vault from the world.

It would have been a foolproof plan, if he hadn't been kicked out of the city, or if the Stone of Golorr hadn't been stolen.

A heretical story

The artwork within the Vault told a story of the ancient history of several deities that dramatically conflicts with established knowledge of them. Specifically, it depicts Dumathoin (the dwarven god of secrets), Ilsensine (the god of mind flayers), and Laduguer (the god of duergar) as being friends. And not just friends, but if the art is to be believed it seems they cooperated with one another on the creation of dwarves.