Finn was born in June 2006, making him 16 years old.
He was born in Brisbane, Australia, but has mastered the American accent for the series.
He may only be young, but Finn quickly become a very respected actor worldwide.
The star has already worked with some huge names including Oscar winner Geoffrey Rush and Jai Courtney.
When he was just 11 years old he made his big-screen debut to critical acclaim.