Jack featured in all 10 episodes of season 1, 6 episodes of season 2 & 7 episodes of season 3, for Game of Thrones.
For amusement between takes when filming Game of Thrones, the English-accented Sophie Turner and the Irish-accented Jack Gleeson, would often imitate each other's accents.
Jack has an Irish accent.
Killinaskully (2006 - 2008) as Pa Connors Jr.
Game of Thrones (2011 - ) as Joffrey Baratheon (King of Westeros)
Moving Day (2002) as Jack (short film)
Fishtale (2003) as Boy with the fish (short film)
Tom Waits Made Me Cry (2004) as Young Vincent (short film)
Batman Begins (2005) as little boy
Shrooms (2007) as Lonely Twin
A Shine of Rainbows (2009) as Seamus
All Good Children (2010) as Dara
Jack is a member of the DU Players at Trinity College.
Bears In Space (2012)
Monster Clock: A Play On Time (2012)
Human Child (2013)
Jack is 5'7" (1.70 m) tall.
Jack has a sister named Hannah.
Jack is a performer and the assistant producer for the Collapsing Horse Theatre Company.
Jack attended Mount Anville Secondary School, moving onto Trinity College, Dublin, when he graduated.
Jack: (about how evil he is in real life) A solid three-and-a-half percent. I'd be lying if I said I was zero. I try to be a nice person, but it's difficult sometimes.
Jack: (on whether villains are born bad or made bad) With Joffrey, the evil and malicious things he does are byproducts of the setting that he's been brought up, how his family behaves, and what he's been made to believe of himself. To me, he's been made bad.
Jack: (his favourite line as Joffrey Baratheon on Game of Thrones) It's when Arya has just humiliated Joffrey by almost beating him up in season one. He's really embarrassed and says, "I've got you, you c***." I didn't like saying it to poor Maisie [Williams] but I loved shape of the words. The line was almost onomatopoeic—a way to verbalise anger and embarrassment. Yeah...I really like that line.
Jack: (about worrying repeating villainous clichés) Definitely. And I think my portrayal of Joffrey is very clichéd. It's something that's so easy to slip into because I've seen so many villainous characters on TV and onstage and in films. Joffrey is definitely informed by those performances.
Jack: (about his audition for Game of Thrones) When I was auditioning for Joffrey. I only had one audition, and the producers and writers were laughing at my performance because I was being so snotty and arrogant. They found it comical. I thought that was good.
Jack: (about rooting for a villain) There's a scene in Psycho, when Norman Bates has just killed Marion and put her in the trunk of a car and he's pushing the car into, like, a lagoon. The scene is so tense and you see his face and he's like, "Oh, please. Can this car just go under..." And you're like, "Yeah, I hope so too, man, and I hope the cops don't come..." But, wait a second, he just killed this girl for no reason! I was rooting for a murderer.
Jack: (describes what influences him as he portrays King Joffrey from Game of Thrones) A big influence was Joaquin Phoenix in Gladiator. Sometimes when I'm sitting on my throne, I think of Phoenix sitting on his, with that smirk on his face.
Jack: (about his favourite villain) The HAL computer from 2001: A Space Odyssey. It's terrifying because it has no empathy, and you can't rationalise with it as you would a human being. As for actors, Rutger Hauer was pretty perfect in Blade Runner. Just his eyes...
Jack: (what currently scares him) I chopped the top of my finger off in a door when I was running away from my cousin about five years ago. Ever since then, I've been very touchy around doors. They scare me a lot.
Jack: (about his fear as a child) There's a big rock called the Skellig Rock, off the West Coast of Ireland, where monks used to go to escape from the Vikings — they'd build their huts on it. I went with my family when I was really young and we had to climb the rock, which is almost vertical at points. That was when I knew that heights really, really freaked me out.