Dark Woods (2020)

S1E5 The Forbidden Room

Fifteen years have passed, and Thomas is now enjoying retirement. However, he remains haunted by his sister's mysterious disappearance. Determined to find answers, he enlists the help of Anne and his former colleague Frank to reopen the case. Their persistence pays off when they interview Heiner, an old friend of Jürgen's, leading to a significant breakthrough in their investigation.