He had lead roles in The Borderers (1968–70), Tom Brown's Schooldays (1971), Budgie (1971–72), its spinoff Charles Endell Esquire (1979–80), Danger UXB (1979) and Sutherland's Law (1973–76), as well as the films The Railway Children (1970), and Gorillas in the Mist (1988).

He guest starred in many prominent British shows including The Avengers, Dr. Finlay's Casebook, The Onedin Line, Survivors, Ripping Yarns, Doctor Who, Z-Cars, Juliet Bravo, Rab C. Nesbitt, Minder, Inspector Morse and Agatha Christie's Poirot.

During that time he was ordered to act as prisoner's friend (defence counsel) at the court martial of a soldier accused of appearing late on parade and then assaulting his superior officer when he eventually did turn up.

[citation needed] Cuthbertson started acting at the Glasgow Citizens' Theatre in 1958 and became General Manager and Director of Productions in 1962.

In that year the theatre hosted an exhibition of work by the artist Stewart Bowman Johnson[3][4] He played William Wallace in the Edinburgh International Festival production of Sydney Goodsir Smith's play, The Wallace, in August 1960, giving what the playwright Robert McLellan described as "one of the few great performances in the history of the Scottish Theatre".

The major cast members included Cuthbertson (as John Sutherland), Gareth Thomas, Moultrie Kelsall, Victor Carin, Martin Cochrane, Maev Alexander and Edith MacArthur.

Although he avoided live theatre work thereafter, owing to a fear of forgetting or stumbling on lines, he was still able to take parts in films and television.