A man gets a newspaper article stuffed anonymously into his mailbox.
It tells of an old friend who murdered 2 people and turned the gun on himself. He writes to a mutual friend about how unsettled he is.
The man becomes so unsettled he begins his own investigation into how his old friend became the kind of man who could kill.
He finds out more than he wanted to know.
I am not certain if this is authentic, but if so, 3 people are still missing.