From publisher blurb:
A gorgon (Greek gorgon, not gas-breathing metal bull) named Nyria setup a lair in an old, forgotten catacomb, which she transformed into a subterranean gallery of sorts using petrified victims that she would "modify" to various degrees, including breaking them apart and bonding parts to other statues.
The PCs are her latest acquisitions.
The good news is she was slain before she had the chance to add them to her collection. Everything she'd ever petrified turned back to flesh. This includes both creatures and numerous sections of the catacombs that she'd renovated using leftover chunks of stone from her "art supplies".
The bad news is that her various art projects either died immediately or shortly thereafter. Due to Nyria’s choice of lair--a catacomb--in most cases either their souls could not pass on, or their corpses were possessed by demonic entities from the underworld.
An undead-infested catacomb is bad enough, probably even worse than if it was inhabited by just a lone gorgon, but the PCs were unconscious before they were brought there: they have no idea where they are or how to get out, and no tools to defend themselves with.
If they want to escape, they’ll need a combination of cunning and luck to literally carve their way to freedom.
This adventure is for Dungeons & Delvers: Black Book, intended for 0-level PCs (the rules were originally presented in an early issue of Appendix D, but have been reprinted here for convenience), but with minimal tweaking would also work for 1st-level PCs.