Born in New Zealand, Mr. Kneebone received his theatrical training at the Bristol Old Vic. In 1959, he toured North America with the London Old Vic Company. He left the company in New York to immigrate to Canada.

Mr. Kneebone's first Canadian role was in a production of She Stoops to Conquer at Toronto's Crest Theatre. In 1966 he starred opposite Zoe Caldwell in Misalliance at the Shaw Festival, and in 1969 he joined the Stratford Festival company for a Christmas production of Sauerkringle at the National Arts Centre in Ottawa. He returned to Stratford in 1975 to play the Dauphin in Saint Joan, Feste in Twelfth Night, Sergeant Kite in Trumpets and Drums and the Reverend Canon Chasuble in The Importance of Being Earnest. In 1976 he played Puck in the Festival's production of A Midsummer Night's Dream, with Hume Cronyn as Bottom and Jessica Tandy as Hippolyta/Titania.

In 1987, Mr. Kneebone became the artistic director of the Smile Theatre Company, "Canada's only professional theatre company dedicated to performing in seniors citizens' homes, care facilities, hospitals and activity centres." Smile creates one hour musical productions, often exploring Canada's heritage, and presents them to senior citizens who would not otherwise be able to enjoy live theatre.

Mr. Kneebone himself wrote and directed many of the company's productions including, most recently, Sweethearts, which toured Ontario in the summer of 2003. Among the performers in the Smile troupe is Dinah Christie, with whom Mr. Kneebone had a long working relationship, beginning in the 1960s at the Buttery in Niagara-on-the-Lake.

In addition to his stage work, Mr. Kneebone acted in film and television, including the Canadian movies "The Luck of Ginger Coffey" (1964) and "The Housekeeper" (1986). He was appointed to both the Order of Canada (as a Member) and the Order of Ontario in 2002.