He has since had roles in films such as The Dark Knight Rises (2012), Starred Up (2013), Lost River (2014), Mississippi Grind (2015), Rogue One (2016), Darkest Hour (2017) and Ready Player One (2018).

[3][4] His father is a prominent medical researcher who previously headed the Howard Florey Institute in Melbourne, where he maintains the status of Professor Emeritus.

[5] Ben and his two brothers, Tom and David, as well as his mother (deceased), a registered nurse, lived in Europe and the United States for long periods of time, and returned to Melbourne when he was in primary school.

[citation needed] In October 2009, he was featured in an episode of the Australian series Who Do You Think You Are?, which traced the ancestry of his paternal grandfather Oscar Mendelsohn, who was from a Jewish family.

[9] His next major role was in The Big Steal (1990), and Spotswood (1992), co-starring with Anthony Hopkins;[10] this was followed in 1994 by Metal Skin[11] and in 1996 by Cosi and Idiot Box.

[citation needed] In 2005, he was preparing to play Mark Antony in the Sydney Theatre Company-produced Julius Caesar,[12] and he was in the Terrence Malick-directed film The New World.

In 2010, he appeared in Animal Kingdom, starring in the film as Andrew "Pope" Cody, a criminal on the run from the law living in the notorious Melbourne Underworld.

[14] In 2012, Mendelsohn played the supporting roles of villain John Daggett in Christopher Nolan's The Dark Knight Rises and Robin Van Der Hook in Derek Cianfrance's The Place Beyond the Pines.

The following year, he appeared in the critically acclaimed Starred Up, directed by David MacKenzie, for which he won Best Supporting Actor at the British Independent Film Awards.

[18][19] In 2016, he appeared in video as an onstage "stand-in" during the Nostalgic For the Present concert tour of Australian singer Sia, for her song "Breathe Me".

[21] A couple of years later in 2018, he played the role of Nolan Sorrento in Steven Spielberg's science fiction film Ready Player One.