O'Conor, a talented young dramatic actor, has made a significant impact in the film and television industry. Born in Ireland, he began his acting career at the tender age of eight.
Before becoming a household name, O'Conor co-starred with Liam Neeson in the British-made feature film "Lamb" (1985). He played the role of Owen, a lonely and epileptic boy who is temporarily rescued from a violent and oppressive children's home by Brother Sebastian.
Three years later, O'Conor landed another major film role as the youthful version of Martin Sheen's narrator in the 1988 film adaptation of Hugh Leonard's heartwarming Tony-winning play "Da".
O'Conor's next film was the critically acclaimed "My Left Foot" (1989),directed by Jim Sheridan. In this film, he played the lead role of a child, depicting the story of the severely handicapped writer Christy Brown.
In 1993, O'Conor appeared in the big-budget remake of "The Three Musketeers", playing the role of the Boy King Louis, who is protected from assassination by the title characters.
O'Conor's first starring role came with Ben Ross' dark British comedy "The Young Poisoner's Handbook" (1995). In this film, he played the role of an amateur toxicologist who is unwisely paroled from prison after testing his theories on family and friends, with fatal results.
Based on a true story, "The Young Poisoner's Handbook" was a thoroughly unpleasant bit of work, yet found an appreciative audience. The following year, O'Conor played a teenager trying to form a rock band in 1959 Russia in the film "Red Hot" (1993).
