Shearing established a name for herself on radio in the 1940s and 50s, co-starring on the soap opera Dr. Paul as the "other woman," Virginia Martin, from 1948 through roughly 1960s. She was heard in Dossier on Dumetrius (1951, as Hedy), the first of several serial thrillers featuring M15 agent Gregory Keen, and in several episodes of The Clock (1955), remade from 1940s American scripts.
Shearing's most notable starring role was on the historical serials Tudor Princess and Tudor Queen (both 1954), playing Elizabeth I of England from age 16 until age 70. She continued to act on Australian radio into the 1970s (including the serials Strange Homecoming and A Relative Affair) and on BBC radio in the 1990 play Summer of Aliens. She was also active on stage.
On television, Shearing was a regular on The Sullivans as Mary Sullivan (1981-1982) and recurred during the final season of the Disney Channel series Five Mile Creek in 1985, appearing in five episodes as the ruthless Mrs. Armstrong. She made guest appearances on A Country Practice, The Lost World, and All Saints.
- Farscape - voice of Elack's Pilot