Edgerton was born in Blacktown, New South Wales, the son of Michael, a solicitor and property developer, and Marianne Edgerton.He graduated from The Hills Grammar School in 1991. He attended the Nepean Drama School at the University of Western Sydney, before moving on to various stage productions, most notably at Sydney Theatre Company.
Edgerton has appeared in such films as Erskineville Kings, King Arthur, Ned Kelly, and as a young Owen Lars in Star Wars Episode II: Attack of the Clones and Star Wars Episode III: Revenge of the Sith. He played Will on The Secret Life of Us, for which he was nominated for an AACTA Award. In 2005, he lent his voice to the title character of The Mysterious Geographic Explorations of Jasper Morello, an Academy Award-nominated animated short film. The same year, he appeared as the son of a deceased shoemaker in the British comedy Kinky Boots. He also appeared in Smokin’ Aces (2006).
Edgerton appeared in the film Whisper (2007), The Square (which he co-wrote and was directed by his brother), Acolytes, and Separation City. In 2009, he starred alongside as Stanley in the Sydney Theatre Company’s acclaimed production of A Streetcar Named Desire. He appeared in a production of the same play at the Brooklyn Academy of Music in December 2009. He starred as an MMA fighter in the MMA film Warrior (2011).
In February 2010, Edgerton was cast in Matthijs van Heijningen Jr.’s 2011 prequel to The Thing, portraying helicopter pilot Sam Carter. He played Tom Buchanan in Baz Luhrmann’s 2013 remake of The Great Gatsby. He was honoured for his work in international roles with the 2011 Australians in Film Breakthrough Award. In June 2013, he was added to the Jeff Nichols film Midnight Special. In September 2013, he was reported to be in talks with Warner Bros. to star in the film adaptation of Shantaram.
In 2014, Edgerton starred in the biblical film Exodus: Gods and Kings, as Ramesses II, Moses’ adoptive brother, who became a notorious king. He will co-star in the 2015 film Black Mass as John Connolly, FBI contact and childhood friend of notorious gangster Whitey Bulger.