- Fell in love with acting while performing in school plays and joined Gaiety's Youth Theatre Company.
- Made screen debut opposite his father Brendan Gleeson in 2006's The Tiger's Tail, directed by John Boorman.
- Came to prominence in 2010 as Hughie Power in the Irish TV series Love/Hate.
- Hollywood took notice in 2012 and was cast as Gus in Snow White and the Huntsman.
- Realized a dream come true in 2015 when he appeared on stage with his dad and brother, Domhnall, in The Walworth Farce in Dublin, during a sold-out run.