A winner of multiple New Zealand Film and TV Awards, Julian Dennison first wowed the audience as a child prodigy with his performance in the drama film Shopping (2013). In 2016, the young actor starred alongside Sam Neill in Taika Waititi`s adventure comedy-drama Hunt for the Wilderpeople, which opened to near-universal critical acclaim and went on to become the highest grossing New Zealand film till date. Dennison`s performance in the movie earned Empire and Saturn Awards nominations, besides winning him a Best Actor honour at the New Zealand Film and TV Awards that year.

Dennison subsequently made his Hollywood debut in 2018 with the superhero movie Deadpool 2, where he essayed the role of Marvel comics character Russell "Rusty" Collins aka Firefist. Other significant acting credits include the family drama Paper Planes (2014) and the sci-fi comedy-drama Chronesthesia (2016). His other releases include Deadpool 2 (2018), The Christmas Chronicles 2 (2020) and Godzilla vs. Kong (2021).