In the early 1970s, they toured for more than four years in the original Australian production of My Fair Lady and presented Gilbert and Sullivan in two-person entertainments throughout the United States and Canada.
Pinafore, Samuel in The Pirates of Penzance, Guron, and Antonio, which he performed in a BBC broadcast from the Savoy Theatre during the company's 1932–33 London season.
Roles in which he occasionally deputised for Fancourt or Sydney Granville were King Hildebrand in Princess Ida, the Pirate King in The Pirates of Penzance, Earl Mountararat and Private Willis in Iolanthe, Colonel Calverley in Patience, Sir Roderic Murgatroyd in Ruddigore, the title role and Pooh-Bah in The Mikado, Wilfred Shadbolt in The Yeomen of the Guard, and Don Alhambra in The Gondoliers.
[6] In 1942, Walker succeeded Granville as principal "heavy" baritone, playing the Sergeant of Police in The Pirates of Penzance, Shadbolt, Don Alhambra, and Pooh-Bah.
[7] The Gilbert and Sullivan historian Colin Prestige wrote of him, "Richard Walker knew exactly the limit between comedy and buffoonery.
[9] Beginning in 1947, both Walker and Roberts began losing roles to other performers engaged by the company,[10] despite their continuing to garner excellent reviews.
Walker was doing concert work and had returned from a production of The Gondoliers in Limerick, Ireland, in 1949, when D'Oyly Carte asked him to step in as an emergency replacement, initially filling in as Grosvenor in Patience (Prestige wrote that his "interpretation ... can only be described as magnificent")[8] and then Bouncer, Counsel, Bobstay, Pish-Tush, the Lieutenant, and Giuseppe in The Gondoliers for the remainder of the season.
[8][14] After his last season with D'Oyly Carte, Walker and Roberts were engaged by the J. C. Williamson Gilbert and Sullivan Opera Company, and toured Australia and New Zealand throughout the 1950s and early 1960s.
When the Williamsons played Gilbert and Sullivan, as they did for extended tours every five or six years, Walker sang his familiar roles, as well as Dick Deadeye in Pinafore and Sergeant Meryll in Yeomen, and he directed the operas.
From 1959, they toured for more than four years in the original Australian production of My Fair Lady, Walker as Alfred P. Doolittle and Roberts as Mrs. Eynsford-Hill.
President Eisenhower asked them to give their concert programme at his pre-inauguration party at the White House following his re-election in 1956, but they were unable to attend, as they were then in Australia.