7. John Wayne Gacy (Gacy)
Gacy is a character scary because of the reality of the situation. He was a married man that seemingly lived a normal life. Behind closed doors, he was a ruthless killer that had at least thirty three victims by the time he was caught. Although the movie he inspired was a movie basically depicting his life exactly, it is a bit odd that he is a man who is also known as the "Killer Clown" because of his dressing up as one to lure little boys to their murder. The reason that's odd is because a few years after he was caught and convicted, a similiar story written by Stephen King came out, with a very close plot. Gacy was a man who dressed as a clown and killed only small boys. "It" was a clown that targeted a specific group of young boys. Coincidence or something more? Whatever the case, Gacy is one of the more infamous serial killers of the 1900s and that is shown in the movie bearing his last name. The next serial killer is actually one without a name. They don't have a name because they were never found, but the movie they inspired is one of the most terrifying of the last decade.