If you liked "The Returned" ("Les Revenants"), "Glitch", "Us", or even "Pet Sematery", you'll have much to like in the Icelandic series "Katla". Eerie, dark, forbidding (often literally so, as the nearly deserted town of Vik, Iceland, has been showered with ash from the Katla volcano for a year), and gripping, the plot moves somewhat slowly but is always engaging.
The story and setting are so grounded in a harsh, otherworldly, and unforgiving environment that the impossible becomes strangely believable. That the characters are tough, realistic, unfanciful sorts adds to the credibility of the supernatural events that befall them.
As each episode ends with a cliffhanger, it's very hard to stop watching. Just one more episode!