During the mid-1960s, the people of America became accustomed to opening their newspapers to two types of headlines. The first would be positive and often have something to do with the space program, perhaps which mission was in the works or which one had just been completed. Then there would be an article of a more negative nature, often concerning the United States' increasing involvement in the Vietnam War. Toward the end of 1968, however, a new and more sinister headline began to pop up. At first it was just in California and seemed to be simply a random crime, with a couple being murdered a few days before Christmas. It was a tragic tale, but in California, it was often dismissed as a byproduct of the youth culture of sex, drugs, and rock and roll that often led young people to be in the wrong place at the wrong time. Then, some months later, another couple was shot, and this time the man survived. The story he told was not of someone targeting either him or his friend, but of a type of madman shooting them again and again. The idea that there was an unhinged serial killer on the loose was confirmed when he began writing letters to the police and the newspapers, not only claiming responsibility for these killings but for others that either had been or would be committed. After he stabbed a third couple and then shot a cab driver in cold blood, he began to send more and more letters. These, like the earlier ones, were signed with a symbol understood only by the killer, a man who called himself "Zodiac".