La Fórmula secreta (+ Audio CD)

Enrique Alvarado goes back to his house in Potes, Cantabria, for the holidays. He has an appointment with Mr Otero, a famous retired chemist, who wants to show him an important discovery. Suddenly Mr Otero disappears without a trace. Enrique and Camila, a childhood friend, start investigating to find their friend and work out his discovery…