Jack Gleeson, born on May 20, 1992, in Ireland, is an actor who achieved global fame for his chilling portrayal of one of television's most hated villains. He is best known for his role as the sadistic young king Joffrey Baratheon in the HBO epic fantasy series Game of Thrones, a performance that earned him critical acclaim and made him a household name despite his character's immense unpopularity. Gleeson's ability to bring such a loathsome figure to life with unsettling depth marked him as a standout talent in a sprawling ensemble cast, but his career took an unexpected turn when he chose to step away from the spotlight at the height of his fame.

Gleeson began acting as a child, making his film debut in the 2002 movie Reign of Fire and later appearing in Christopher Nolan's Batman Begins in 2005, where he played a young boy. His early work also included roles in Irish productions such as Shrooms and the television film The Poor Mouth. However, it was his casting in Game of Thrones in 2011 that catapulted him to international prominence. As Joffrey Baratheon, Gleeson portrayed a cruel, cowardly, and power-hungry monarch whose brutal actions, from ordering executions to tormenting his family, made him a central antagonist of the series. His performance earned him widespread praise from critics and audiences alike, though it also led to real-life hostility from fans who struggled to separate the actor from his character.

Following his character's shocking death in the fourth season of Game of Thrones in 2014, Gleeson announced a six-year hiatus from screen acting. He cited a desire to pursue academic interests and a lack of passion for the industry at that time, enrolling at Trinity College Dublin to study philosophy and theology. During his break, he focused on his studies and occasionally participated in theater projects, including a role in the play "Bears" at the Dublin Fringe Festival. This period of reflection allowed him to reassess his career path.

Gleeson made a highly anticipated return to screen acting in 2020, appearing in the Irish comedy series Out of Her Mind. He continued his comeback with a role in the 2023 Irish film In the Land of Saints and Sinners, a thriller set in 1970s Ireland starring Liam Neeson. In 2025, he expanded his television work by appearing in the Netflix series The Sandman, based on the acclaimed comic by Neil Gaiman, and in the historical drama House of Guinness, a series exploring the famous brewing dynasty. These projects marked a new chapter in Gleeson's career, demonstrating his versatility and willingness to take on diverse roles after his long absence. Today, Jack Gleeson remains a respected figure in the entertainment industry, known for his powerful early performance and his thoughtful, deliberate approach to his craft.