On tonight’s episode,
Lydia, who recently discovered a bit of scrambled code left to her by her late grandmother, finally uncovered its elusive cypher key with Stiles‘ help. Once she plugged in “Ariel,” the code condensed into a list of 10 people around town who had recently killed themselves at Eichen House — Lydia’s grandmother Lorraine, among them — and so the duo traveled to the mental health facility for more information.