[3][4] He moved to London appearing in a variety of roles most notably as Dr Grimwig in Oliver!, Lionel Bart's acclaimed Dicken's musical, at the New Theatre.
[2] Robertson also wrote and performed his own one-man show, Your Humble Servant, at the Open Space Theatre, London.
[4] Other notable television appearances include The Ambassadors of Death, a Doctor Who serial in 1970 and the role of Palanguez in the BBC's The Day of the Triffids.
[2] On the big screen Robertson appeared in the 1996 film Breaking the Waves, directed by Lars von Trier.
[2] Robertson died on 17 January 2001, at the age of 70, after suffering a heart attack while reading a Robert Burns poem, Holy Willie's Prayer, on stage in Perth.