Benedict Cumbermatch and his striking transformation in order to play Australian WikiLeaks founder Julian Assange. This is revealed in the new trailer for the controversial movie entitled "The Fifth Estate."

The Sherlock star grabs Julian Assange's Australian accent with skill, however Assange is not likely to be impressed. The WikiLeaks founder has criticised the movie as propaganda designed to fan the flames of a war against Iran.

"Man is least himself when he talks in his own person. But if you give him a mask, he will tell you the truth," he tells an adoring crowd in his Australian accent.

The film involves how WikiLeaks started, undertaking the US response and Assange's growing ego. It is grounded on former WikiLeaks staffer Daniel Domscheit-Berg's tell-all book WikiLeaks: My Time With Julian Assange at the World's Most Dangerous Website.

The trailer shows Assange viewing US military video of American soldiers killing weaponless journalists in Iraq, taking on tyrannical regimes, going after crooked bankers as well as the colossal leaking of US government confidential documents.

It also may touch on Assange's sexual assault accusations, with a scene of him undoing his shirt with a woman.

Laura Linney and Stanley Tucci will be in the film as US officials frantic to stop the leaking of the United States secrets. The film will be released in the US in November this year, but there is no Australian release date yet.

Early this year, Assange disparaged the film after getting a copy of the script.

Assange said that it is a mass propaganda attack against WikiLeaks.

Assange is wanted in Sweden due to the sexual assault allegations. He was granted asylum by the Latin American nation and remains inside Ecuadorean embassy in London.