Charles Nelson Reilly was born to Charles Joseph Reilly and Signe Elvera Nelson. His father was Irish-American and Catholic, his mother was Swedish-American and Lutheran. As a child he amused himself with improvised puppet theater performances.
He had a traumatic experience in 1944, when present for the Hartford circus fire in Hartford, Connecticut. A fire during a performance of the Ringling Bros. and Barnum & Bailey Circus killed 167 people and injured 700 people. While Reilly was one of the survivors, he was left with a life-long fear of fires. He never attended public performances of theater and circus again, as an audience member, for fear of another fire.
Reilly wanted to enter show business as a youth, and in particular to become an opera singer. He took lessons at the University of Hartford Hartt School, but eventually realized that his voice skills were inadequate. He turned to theater next, and debuted in film with a bit role in “A Face in the Crowd” (1957). During the late 1950s, Reilly appeared regularly in comic roles in theatrical performances Off Broadway.
In 1960, Reilly first gained critical attention, for a small but noteworthy part in Broadway musical “Bye Bye Birdie”. In 1961, Reilly joined the cast of the musical “How to Succeed in Business Without Really Trying”. He won his first Tony Award in 1962 for that performance. He kept appearing in Broadway shows for the rest of the decade.
As a notable actor, Reilly started making television appearances in the 1960s. He started as a guest in panel shows and as a player in television advertisements. He eventually gained a key role in the television series “The Ghost & Mrs. Muir”, where he appeared from 1968 to 1970. In the 1970s, Reilly was a regular in game shows and children’s series, such as “Match Game” and “Uncle Croc’s Block”.
In 1976, Reilly started teaching acting to others, while shifting his own career from acting to directing. He directed Broadway shows regularly and was nominated for a Tony Award for directing in 1997. He also directed a number television episodes. In the 1990s, he had guest roles in television series such as “X-Files” and “Millennium”.
In the 2000s, Reilly was primarily known for the autobiographical play “Save It for the Stage: The Life of Reilly”, and for its film adaptation. While touring the United States, he developed respiratory problems which led to his retirement. His illness got worse, and he died due to pneumonia in 2007.
