He was born Colin James Farrell in the Castleknock area of Dublin, at the edge of Phoenix Park, on March 31st, 1976. The place was fairly well-to-do, a new money suburb, but Colin came from resolutely working-class stock.Colin's father Eamon and his uncle Tommy both played football for Shamrock Rovers. At their Sixties peak they were the Manchester United of Ireland. Colin was the youngest of four, his brother Eamon now running a performing arts school in Dublin, while sisters Catherine and Claudine have both popped up in Colin's movie productions.

Farrell studied acting at the Gaiety School of Drama in Dubin and has already established himself as a recognizable talent back home with a starring role in the BBC series Ballykissangel and Dierdre Purcell's miniseries Falling for a Dancer, in addition to a featured role in Tim Roth's directoral debut, The War Zone. Colin Farrell made his North American theatrical debut in the dramatic movie, "Tigerland," directed by Joel Schumacher. "Tigerland" followed a group of American soldiers as they prepared for the Vietnam War by participating in war games in the backwoods of Louisiana. Since then, Farrell's gone on to star in such diverse films as "The Recruit," opposite Al Pacino, and "Daredevil," where he played the role of the villain 'Bullseye' with devilish charm. He teamed up again with director Joel Schumacher for "Phone Booth," a movie that was delayed for many months due to the real-life sniper shootings in Washington. In "Phone Booth," Farrell portrayed a man pinned down in a phone booth by an unseen sniper.

Farrell also starred alongside Kevin Spacey in Thaddeus O'Sullivan's Dublin gangster movie, Ordinary Decent Criminal. It was Spacey who suggested him for the part after catching Farrell's riveting performance in the play, In a Little World of Our Own at the Donmar Warehouse in London. Farrell took on the role of Jesse James in American Outlaws. He also co-starred with Bruce Willis in Hart's War which was shot on location in Prague, Czech Republic. He also starred in Stephen Spielberg's Minority Report alongside Tom Cruise, Samantha Morton, and Max Von Sydow. Known for his quick wit, expletive-filled language, and devil-may-care attitude, Farrell has risen fast and as of 2003, is one of the most sought after actors in Hollywood.