Ric Throssell was the son of novelist Katharine Susannah Prichard, and Gallipoli Victoria Cross winner Hugo Throssell. He was educated at Perth's Wesley College, and then attended Clermont Teachers' College, where he also enrolled in classes at the University of Western Australia. During World War II, he enlisted in the Australian Army, and served for a period in New Guinea. In 1943 he joined the Department of External Affairs, and was subsequently posted to Moscow (1945-1946) and Rio de Janeiro (1949-1951). During the late 1940s he acted as an adviser to Labor Foreign Minister H. V. Evatt, during Evatt's term as President of the United Nations General Assembly. Suspected of having Communist links, Throssell came under constant surveillance, initially from the West Australian Special Branch, and later from ASIO. In 1955, he appeared before the Petrov Inquiry, but no case could be established against him. Despite the inevitable damage to his reputation, and ongoing behind the scenes moves by ASIO, Throssell continued to pursue his diplomatic career, albeit with reduced prospects of promotion. In 1980, following shifts in official attitudes, he was appointed director of the Commonwealth Foundation in London. He retired from the diplomatic service in 1984.
Throssell's primary artistic interest was undoubtedly the theatre, and during the course of his lengthy association with the Canberra Repertory Society, as a writer, director, and actor, he wrote over 30 works for the stage (most of which remain unpublished). Whilst his oeuvre includes a number of lighter works and experimental pieces, his plays invariably reflect his preoccupation with social and political issues. His best known plays include The Day Before Tomorrow (1956), which explores the horrors of nuclear war, and For Valour (1958), the story of a war hero unable to survive the defeats of peace (which is loosely based on his father's life). A number of his plays have been performed on radio and television. In addition to his works for the stage, Throssell wrote four novels, a biography of his mother (whom he loved and admired), an autobiography, poems, and a number of shorter items and magazine articles. He also edited two collections of his mother's short stories and essays.
In his later years, Throssell became more actively involved in campaigning for peace and nuclear disarmament, and he helped found the Canberra based group, Writers Against Nuclear Arms. He died in Canberra in 1999, following his wife and companion of over 50 years, Dorothy.