Dorothy Kilgallen

A famous crime reporter at the New York Journal American. Opposed to the Warren Commission's conclusions, she personally met Jack Ruby in jail (without any witnesses, guards included), and then declared she had revelations to make about the JFK assassination in a book.

But she died of an alcohol and barbiturate overdose in November, 1965. Two days later, her friend (and occasionally co-worker) Earl Smith also died, officially of a heart failure.