An accident occurs in a chemical industry in Milan causing the escape of some poisonous gas. The management keeps the true nature of the gas a secret from the general public. A press-agent of the factory gets hold of some secret documents and so she goes to a mountain refuge to decide what to do about them. The management tries to prevent the circulation of the papers. The woman falls down the mountain and dies but she leaves behind a cassette on which is recorded the proof of how the accident in the factory happened.