Among his notable television credits are the Apostle Andrew in Son of Man by Dennis Potter (1969); the Earl of Kildare in The Shadow of the Tower (1972); George Stephenson in the Doctor Who serial The Mark of the Rani (1985) and Lesley Flux in Midsomer Murders episode The House in the Woods (2005).

[7] From February to April 2012 Grainger performed as Mr Balance in The Recruiting Officer, the 1706 late Restoration Comedy by Irish playwright, George Farquhar.

As a result of the particular interest generated in Grainger's life over the course of the production, Mark Gatiss, his fellow cast member, instigated a Platform event which took place before the evening performance of The Recruiting Officer on 11 April.

During the discussion, Grainger confirmed some little known facts about his life and told anecdotes about his career over sixty years as both actor and playwright in the UK and US.

He expressed gratitude to his father for bringing him along as a small boy to theatrical events which he humorously described and which had a positive effect on his imagination and determination to engage with performance.

Following a distinguished acting career, most particularly at the National Theatre in London, Grainger worked on writing projects in the 1980s whilst his children grew up.