He was one of America's most feared men and a serial killer.
From the comfort of his home, Ted Kaczynski would make bombs before concealing them in letters and sending them to unsuspecting victims.
He was a mastermind who killed three people and injured more than 20 through 16 lethal package bombs.
He was a brilliant mathematician who believed he was a rebel with a cause.
Between 1978 and 1995 he sent the bombs to universities and airlines and was finally arrested in 1996.
He was sentenced to a life behind bars two years later.
But now Mr Kaczynski, labelled the "Unabomber", has contacted the media to tell his side of the story.
His brother, David, published a book in February that spoke about the "Unabomber" and his deranged state.
"Ted was a brilliant, yet troubled, young mathematician and a loving older brother," a book preview said.
"But as Ted grew older he became more and more withdrawn, his behaviour became increasingly erratic, and he often sent angry letters to his family from his isolated cabin in rural Montana."
The "Unabomber" refused to accept his brother's words and decided to write a letter to a handful of journalists.
Staff writer for the New Yorker, Lawrence Wright, was one who received the letter and he posted it to Twitter.
"Dear Mr Wright," it said.
"I am writing because I am ready to speak to someone from the media regarding my brother's recent comments and to discuss how they are being used to torment me.
"I am only granting one interview to one person. In order to determine who will get the interview, I am asking you to write me back affirming that you understand that I am NOT mentally ill, as my brother Dave, would have you believe.
"Since I have no way of knowing which one of you will actually report this fact, I am asking a select few people, who have written to me in the past, to write me and 1) tell me who you are and 2) why should I trust you."
Mr Wright captioned his tweet "thanks Ted. You're not nuts at all."
Mr Kaczynski believed his bombings were vital to highlight how technology was destroying human freedom.
We will have to see whether Mr Wright will take up the opportunity to hear the "Unabomber's" side of the story, with him remaining tight-lipped about his intentions.