WaPo Berlin 4 сезон 5 серия — Эпизод 5

The body of 17-year-old boarding school student Alina Kowalewa is found in Lake Tegel. The girl had already been missing for two weeks. The cause of death is a gunshot wound to the head, and her body was deliberately submerged in the lake. Who killed the seventeen-year-old, who was described by everyone as a model student?