Netflix description: "When a young boy vanishes, a small town uncovers a mystery involving secret experiments, terrifying supernatural forces and one strange little girl."
Rotten Tomatoes critic score: 93%
What critics said: "It's a real and joyful return to form for the show that has been taken fiercely to the hearts of people who weren't there the first time round and, perhaps even more fiercely, by those who were." — Guardian (Season 3)