Netflix and Hasbro Entertainment are going all-in on some deep geekery. Alfonso Cuarón (Gravity, Y Tu Mama Tambien, Harry Potter & The Prisoner Of Azkaban) is along for the ride. Cuarón will executive produce Ravenloft. This will be a live-action TV series to be based in the Dungeons & Dragons universe.
The project is completely separate from The Forgotten Realms, another live-action series also set in the same universe. That was also in development at Netflix under Shawn Levy but now appears to be parked.
Ravenloft is said to be a “character-driven prestige supernatural fantasy series” that will blend adventure with gothic horror, dark magic, and tragic romance. Ravenloft tells the story of vampire Darklord Strahd von Zarovich, whose story of power, love, obsession, and transformation follows his journey from tragic antihero to notorious villain.

According to Wikipedia, which is the source for the sum total of my D&D knowledge:
“Ravenloft is a campaign setting for the Dungeons & Dragons roleplaying game. It is an alternate time-space existence known as a pocket dimension or demiplane, called the Demiplane of Dread, which consists of a collection of land pieces called “domains”, brought together by a mysterious force known only as the Dark Powers. Each domain is tailored to and mystically ruled by a being called a Darklord who is forever trapped and surrounded by magical mists surrounding the domain.”
OK then. Introduced in 1983 by Tracy and Laura Hickman, Ravenloft is one of the most played Dungeons & Dragons settings.
Writer/executive producer John August (Corpse Bride, Frankenweenie) is onboard, with Gabriel Marano, Richard Schwartz, and Gaby Rodriguez also executive produce.