Brían Flynn O'Byrne was born in County Cavan, Ireland. After training at the Samuel Beckett Center and Trinity College in Dublin, the twenty-something O'Byrne moved to New York City to pursue an acting career. He landed minor parts in several short films and on the sitcom "Valerie's Family" (NBC, 1986-1991). He also starred in a few Irish feature dramas such as "The Last Bus Home" (1997) and "The Fifth Province" (1997), the latter of which saw him portray a tormented writer in search of a mythical province that promises magic and passion. While he built up his TV and film acting credits, O'Byrne also had a thriving career on stage. His memorable performance in the 1998 Broadway production of "The Beauty Queen of Leenane" earned him a Tony nomination for Best Actor that year, followed by another Tony nod for Best Actor in 1999 for his role in "The Lonesome West." The year 2004 had several milestones for O'Byrne. Not only did he win that year's Tony Award for Best Actor for portraying a sympathetic child murderer in the off-Broadway production of "Frozen," he also won a Drama Desk Award for Outstanding Actor for his compelling performance as a personable child-molesting priest in the play "Doubt."In 2004, O'Byrne co-starred in the critically acclaimed drama "Million Dollar Baby" as a priest who dissuades a boxing trainer (Clint Eastwood) from performing euthanasia on his fallen and disfigured protégé (Hilary Swank). In the late 2000s, O'Byrne's career gained momentum on television. He had a recurring role on the crime drama "Brotherhood" (Showtime, 2006-08) as the lead character's (Jason Isaacs) Irish cousin and right-hand man, and was a regular on the sci-fi series "FlashForward" (ABC, 2009-2010), about a mysterious event that causes everyone on Earth to simultaneously lose consciousness for a few minutes and see visions of their future. In 2011, he co-starred on the television remake of the mini-series "Mildred Pierce" opposite Kate Winslet, Guy Pearce, and Evan Rachel Wood. Based on James M. Cain's 1941 novel and set in post-Depression America, the series followed Winslet's character, a single mother trying to raise her children without her first husband, played by O'Byrne, whom she threw out of the house after she caught him cheating. For his portrayal of a surprisingly likeable character on the series, O'Byrne earned a 2011 Emmy nomination for Outstanding Supporting Actor in a Miniseries or a Movie.