Aidan Quinn began his acting career at age 19, initially appearing in plays staged at Chicago theatres. He later made the move to film, making his film debut in the 1984 romantic film Reckless, where he played the lead character Johnny Rourke. This was followed by a role in Desperately Seeking Susan, as the male lead Dez. He gained further recognition in the television movie An Early Frost, playing the lead role of an attorney who is homosexual and has been diagnosed with AIDS. This earned him his first Emmy nomination.
A setback to Quinn’s career came in 1988, when he was originally pegged for the lead role in the controversial film The Last Temptation of Christ. The film, which depicted Jesus Christ is a different way, was dropped by Paramount Pictures after outcry from several Christians. When Universal Pictures picked up the film, he lost the role to Willem Dafoe. Regardless, he continued to star in films into the 1990s, getting success in releases such as Legends of the Fall, Benny & Joon and The Handmaid’s Tale.
Quinn would later find fame in television programs. Some of his credits include Third Watch, The Book of Daniel, Canterbury's Law and Weeds. In 2011, he joined the cast of NBC's Prime Suspect as Kenny Rowe. After the cancellation of the series, he moved on to star on the CBS series Elementary.