Bob Morane

Sophia secretly takes pictures of a UFO in a cave in Scotland. Back in London, she puts the negatives in an envelope addressed to Bob and drops them in the letterbox. Shortly afterwards she is kidnapped by Patterson, the chairman of a secret organisation called 'Protectors of the Solar System'. When Bob and Bill arrive at the hotel, the doorman wants to hand them Sophia's letter, but a masked man snatches the envelope from him and flees. The friends chase the man to an underground station and confront him there. When he sees no way out, he kills himself in front of them. Bob's curiosity is aroused when he discovers a mysterious bar code on the stranger's neck ...