From publisher blurb:
Level-6 D&D 5e + Shadowdark Adventure
In The Gate of Worlds, a group of curious, fairy scholars delved into the Shrine of the Planar Gate and meddled with eldritch devices left there by an ancient wizardly cabal. In their ignorance, the fairies opened a portal into the Feywild, triggering the immediate entrance of Fey Court Sentinels into the Material Plane. The error was costly; all but one of the fairies were petrified by the strange, merciless, fey entities.
The surviving fairy, Mabelle, and the last representative of the cabal of wizards, Raharad, the Wise, seek valiant adventurers to help them explore the ancient dungeon and close the portal. The wizened mage exclaims that, long ago, there was a terrible war between the two planes and that the portal must be closed immediately. On the other hand, Mabelle is trying to find a way to heal her petrified friends. She insists there must be a way to do that in the old dungeon. The characters' actions shall dictate what happens in the end...