Cumberbatch proud of WikiLeaks film
The Sherlock star admitted the cautionary email he received from the exiled WikiLeaks founder, which he portrays in Bill Condon's movie, made him question his involvement, before "galvanising" him into realising why he signed up.
"To have the man you are about to portray ask you intelligently and politely not to do it gave me real cause for concern. However, it galvanised me into addressing why I was doing this movie," the British actor wrote during a Reddit Ask Me Anything (AMA) session.
Julian snubbed Benedict's request for a meeting, and warned him that he would be "used as a hired gun" in his email.
The 37-year-old Star Trek Into Darkness actor continued: "He accuses me of being a 'hired gun' as if I am an easily bought cypher for right wing propaganda. Not only do I NOT operate in a moral vacuum but this was not a pay day for me at all.
"I've worked far less hard for more financial reward. This project was important to me because of the integrity I wanted to bring to provocative, difficult but ultimately timely and a truly important figure of our modern times."
Benedict added: "There is only personal truth in my opinion, and the film should provoke debate and not consensus. It should be enjoyable and ultimately empowering to realise that Julian has spearheaded a movement that is the foundation stone of The Fifth Estate, people journalism and what that is capable of, including finding out the 'truth' for yourself."
Meanwhile, Julian told the Hollywood Foreign Press Association that the Fifth Estate is "destined to be a box-office failure", because audiences prefer "combative underdog" stories.