BTS
- Tahun: 1970
- Negara: Spain
- Genre: Thriller, Mystery
- Studio:
- Kata kunci: behind the scenes, series of murders, locked door, arts school, school project, murder in school, locked inside
- Pengarah: Igor Morales
- Pelakon: Néstor Seller, Juan Paya, Lucía Agustín, Irene Hickey, Candela del Olmo, Álvaro Galarza Lima
