In 2007, Harries toured with the Royal Shakespeare Company, playing The Duke of Albany in their production of King Lear which had Ian McKellen in the title role and Sylvester McCoy as the Fool.
Since 1998, she has played companion Bernice Summerfield in the Big Finish Productions' Doctor Who audio plays, appearing in three Doctor Who audio plays opposite Sylvester McCoy as the Seventh Doctor and Sophie Aldred as Ace, as well as in over 50 audio plays based solely on Bernice.
Sylvester Stallone | Sylvester | McCoy Tyner | Sylvester (Looney Tunes) | Order of St. Sylvester | Andy McCoy | Sylvester McCoy | Neal McCoy | Jason McCoy | Sylvester (singer) | John McCoy | Glenn McCoy | Sylvester Levay | Colt McCoy | Van McCoy | Sylvester James Gates | Pope Sylvester II | Maimie McCoy | Leonard McCoy | James Joseph Sylvester | Sylvester Pennoyer | Sylvester of Marsico | Sylvester Joseph | Sylvester Croom | St. Sylvester's College | Simon McCoy | Michael McCoy | Meredith McCoy | McCoy | Kid McCoy |
Successor Sylvester McCoy and predecessors Peter Davison and Jon Pertwee also appeared as members of a small group joined against a sinister conspiracy.
He subsequently cast the next three actors to play the role: Peter Davison (1981–84), Colin Baker (1984–86) and Sylvester McCoy (1987–89 & 1996).
Ayres's work on broadcast Doctor Who was during Sylvester McCoy's era as the Seventh Doctor, comprising The Greatest Show in the Galaxy, Ghost Light, and The Curse of Fenric.
The series has featured guest appearances from the likes of Norman Lovett, Peter Mullan, Rikki Fulton, Anita Dobson, Timothy Spall, Stanley Baxter, Kevin McNally, Clive Russell, Jerry Sadowitz, Viv Lumsden, Sylvester McCoy, Russell Hunter, Peter Capaldi and then unknowns David Tennant, Ashley Jensen, Ford Kiernan, Greg Hemphill, Karen Dunbar, Jane McCarry and Paul Riley.
Starring John Woodvine as Dr. Bryon Caligari, Victoria Wicks as Anthrax and Sylvester McCoy as Snuff, The Cabaret of Dr Caligari is a macabre comedy about the goings on at a night club owned by Dr Caligari.
Previously Martin appeared in the show itself as a Time Lord in the 1969 serial The War Games opposite Second Doctor Patrick Troughton and later guested in the 1993 Doctor Who radio play The Paradise of Death alongside Third Doctor Jon Pertwee and the 2003 Doctor Who audio drama Flip-Flop alongside Seventh Doctor Sylvester McCoy.
The character of the Minister of Chance (now played by Julian Wadham) is played in a podcast-only audio drama entitled The Minister of Chance, also featuring Sylvester McCoy, Paul McGann and Jenny Agutter.