Barry Keoghan spent just $10 on his self-tape audition for 'The Batman'.

The 30-year-old star tried out for the role of The Riddler in the movie, and while he lost out to Paul Dano, the actor's budget 'Clockwork Orange'-inspired audition tape did enough to impress director Matt Reeves and land him the part of The Joker.

Keoghan, who spent $10 on a cane and a hat for the tape, told Esquire magazine: "I just made it up. I wanted to make it Kubrick-y: symmetrical, the X on the back, the square doorframe, everything square.

"I just wanted swag to come across. Swag and endearing. It was just me giving my idea. And then I's like, 'I’ma send this in!' "

Last month, Keoghan explained his version of The Joker - a character previously portrayed by the likes of Jack Nicholson, Heath Ledger, and Joaquin Phoenix - is "a bit charming and a bit hurt".

The 'Banshees of Inisherin' star told GQ Magazine: "I wanted some sort of human in there behind the makeup.

"I want people to relate to him ... [to know] this is a facade he puts on."

Keoghan was told he had landed the Joker role during a phone call with his agent while he was having dinner with a pal in New York.

His agent told him at the time: "The Batman wants you to play the Joker - but you cannot tell anyone."

Keoghan has been keen to land a comic book character role for years, and in 2013 he tweeted legendary Marvel Comics writer Stan Lee.

The 'Top Boy' star wrote at the time: "@TheRealStanLee Stan Lee, Please make me a SuperHero :). (sic)"