A fourth-generation Dubliner, he was a well-known figure in both his homeland and British television, celebrated for his versatility in both comedic and dramatic roles. His father, Con O'Shea, was an actor and singer who performed as part of the double act "Light and Shade" before becoming an army captain during the Irish Civil War. His mother was a harpist and ballet dancer, and his great-grandfather, who fought in the American War of Independence, inherited a piece of Texas, struck oil, became a gambler in New Orleans, and tragically lost his life in a plague.
He attended the Synge Street Christian Brothers establishment, where he shared a desk with a future British television personality, Eamonn Andrews. After being heavily involved in school theatrical productions, he began his professional acting career at the age of 17, performing regularly with the Gate Theatre in Dublin. He eventually became a director with the Gate Theatre, in addition to running his own company, "The Vico Players."
He starred in the Irish musical "Carrie" at a Dublin festival, before taking it and "King of Friday's Men" on a three-year tour of America. In England, he acted in "Treasure Hunt" under the direction of John Gielgud, and on television, he played the role of Bloom in the BBC's "Bloomsbury," a part he particularly loved.
In 1951, he married actress Maureen Teal, with whom he had a son, Colm. The couple was on their way to America on a working honeymoon when their plane crash-landed in Iceland, where they were stranded for five nights while the aircraft was repaired. Once in America, they joined the Touring Players on tours of Mexico and Florida, performed in summer stock at the De Lys Theatre on Block Island, and, when out of work, operated the elevator at the Waldorf Astoria.
Back in Ireland, they gained a reputation as a team on stage and radio, with their own shows "Maureen and Milo" and "What Are They Talking About." They resided near the sea in Dalkey and had a son, Colm.
