His interest in acting developed at school, where he played several leading parts including Oberon in A Midsummer Night's Dream and the title role in Richard II.
His movements were assured and stylish, his speaking well-contrasted and clear and he showed a mastery of facial expression that made of Joseph a fascinatingly tortuous creature.
[6] His stage roles in subsequent years included Malvolio to Robert Lang's Sir Toby in Twelfth Night (1972);[7] the rebel in Peter Ustinov's The Unknown Soldier and His Wife opposite the author as the Archbishop (1973),[8] and Allmers in Ibsen's Little Eyolf (1975).
[12] In 1989 he played the American orator Patrick Henry in Ludovic Kennedy's BBC television study of oratory, Reason and Intellect".
[14] In the early 1990s he wrote a radio play based on The Baby Grand by the 1920s novelist and short story writer Stacy Aumonier.
[15] In 1986 BBC Radio 3 broadcast a non-fiction work by Usher, a talk in which he "relives a personal pilgrimage to the birthplace of Hector Berlioz".
[19] As a radio actor Usher's range was wide, from farce to tragedy, from classics to modern works, from soap opera to reconstructions of momentous historical events.
[23] He made occasional appearances in two of BBC Radio's long-running soap operas, The Archers and Waggoner's Walk,[24] and at around the same time played Richmond in Richard III.
In this book Usher examined how Elizabeth I's chief minister, William Cecil, helped the queen to restore religious stability to a country wracked by two decades of divisions and uncertainty.
[29] The reviewer in the Sixteenth Century Journal praised the book for correcting two widespread misconceptions about the church history of the period: "it puts paid to the idea that Elizabethan government intentionally exploited sede vacante opportunities; and it gives the reader a clear picture of hardworking, conscientious bishops, laying to rest the old chestnut that they were merely timeserving opportunists.
"[30] The Archive for Reformation History called the book "an example of that comparatively rare genre; a piece of genuinely original research".
The final editing of the manuscript was undertaken by Kenneth Fincham, Professor of Early Modern History at the University of Kent.