His first glint of overseas recognition came the following year, when Farrell was cast in a supporting role in Thaddeus O'Sullivan's Ordinary Decent Criminal, an Irish gangster drama starring Kevin Spacey and Linda Fiorentino. Criminal, which didn't fare well on U.S. shores, was quickly followed by Joel Schumacher's Tigerland. Although the low-key ensemble film, which was set in a Louisiana boot camp in 1971, received a lukewarm reaction from critics and audiences, Farrell's performance was the subject of almost ubiquitous praise.

Quickly labeled as one of the most exciting new actors to be detected by the Hollywood radar, the young Dubliner subsequently found himself enmeshed in the distinctly American phenomenon of almost overnight success; before the year was out, he had secured starring roles in a number of projects, including American Outlaws, in which he starred as Jesse James alongside Scott Caan and Kathy Bates, and Joel Schumacher's Phone Booth, a thriller about a young man (Farrell) fighting for his life inside the titular enclosure. Although the long-delayed Outlaws did little for Farrell's career, far more ticket buyers were able to see the young actor alongside Bruce Willis in the somber POW drama Hart's War in early 2002.

The following year, Farrell was virtually unavoidable. Not only did 2003 see the release of the aforementioned The Phonebooth, is also found the actor on the right side of the law in both The Recruit and SWAT and on the wrong side as the villainous Bullseye in the comic book superhero film Daredevil. As if the year was busy enough, he also turned up in a pair of smaller films, Veronica Guerin and Intermission.

The two ensuing years might not have seen Farrell churning out a half-dozen pictures apiece, but he continued to grow in stature, first with a supporting part in the indie period piece A Home at the End of the World, then the title role in Oliver Stone's ambitious flop Alexander (both 2004). Indeed, Farrell's most notorious appearance around this time was, like so many before him, in a much-circulated sex tape leaked on the Internet. Two major roles in films by well-respected directors followed: The lead in Terrence Malick's critically-acclaimed but, again, little-seen The New World (2005), and the challenging role of author Arturo Bandini in Robert Towne's Ask the Dust. 2006 promised to turn around Farrell's downward box-office spiral with Michael Mann's much-anticipated remake of his own groundbreaking '80s TV show, Miami Vice.

Farrell was named one of People magazine's "50 Most Beautiful People" in 2003. He was also voted sixth in the World's "Sexiest Man" contest by Company magazine that same year.

In 2007, Farrell joined other celebrities including Bruce Willis, Muhammad Ali, Eva Mendes, Vanessa L. Williams and Arnold Schwarzenegger to become an official games spokesman for the Special Olympics World Games in Shanghai, China.