A human chameleon with a deft touch at playing charismatic heels, Aidan Gillen became an intrinsic player to some of the most groundbreaking television shows of the 1990s and 2000s, including such prestige fare as the U.K.'s "Queer as Folk" (Channel 4, 1999-2000) and HBO's "The Wire" (2002-08) and "Game of Thrones" (2011- ). In the early 1990s, the Irish-born Gillen established a footprint in the U.K. theater scene and a run of well-regarded independent films like "Circle of Friends" (1995), "Some Mother's Son" (1996), "Mojo" (1997) and "Buddy Boy" (1999). In 1999, he landed one of the leads on the daring British series "Queer as Folk," one of the first humanizing looks at gay culture in television history. In 2003, Gillen's Broadway debut in Harold Pinter's "The Caretaker" earned him a Tony nomination, setting him up for a memorable splash on U.S. television as Mayor Tommy Carcetti on HBO's magnum opus urban drama "The Wire." Gillen carved a niche playing textured, scene-stealing villains in projects such as "Lorna Doone" (BBC, 2000), "The Final Curtain" (2002), "Shanghai Knights" (2003), "Blackout" (2008), "Freefall" (BBC, 2009) and "Blitz" (2011), capped deftly by his return home to play a mob boss in the Irish drama "Love/Hate" (RTE, 2010-11) and the Machiavellian counselor Littlefinger on "Game of Thrones." That international hit widened his profile even further, allowing him strong supporting roles in films like "The Maze Runner: Scorch Trials" (2015), gang drama "Still" (2014) and Guy Ritchie's "King Arthur: Legend of the Sword" (2017).