(1965), Thomas Cromwell in A Man for All Seasons (1966), Tom Ryan in Ryan's Daughter (1970), Harry Bundage in Candleshoe (1977), Paddy Button in The Blue Lagoon (1980), Dr. Grogan in The French Lieutenant's Woman (1981), Father Imperius in Ladyhawke (1985), and the role that made him a household name as an actor, Horace Rumpole, whom he played in the British television series Rumpole of the Bailey.

[1] On leaving school, he initially worked in a factory, where at the age of 15, he suffered an accident which resulted in the removal of his left eye.

In 1955 he appeared in "The Burnt Flower Bed" by Ugo Betti directed by Peter Hall at the Arts Theatre Club in London.

In 1965, he played the lead in Bolt's The Thwarting of Baron Bolligrew, and Disson in Harold Pinter's Tea Party.

His more notable film appearances included the science-fiction classics X the Unknown (1956), The Day the Earth Caught Fire (1961), the World War I drama King and Country (1964), Help!

(1965), the Academy Award-winning adaptation of A Man for All Seasons (1966), The Shoes of the Fisherman (1968), Ryan's Daughter (1970), Massacre in Rome (1973), The Adventure of Sherlock Holmes' Smarter Brother (1975), The Omen (1976), The Blue Lagoon (1980), The French Lieutenant's Woman (1981) and Ladyhawke (1985).

One of McKern's earliest television roles was in the 1950s black-and-white series The Adventures of Robin Hood (as Sir Roger DeLisle, usurper of the Locksley manor and lands, and Herbert of Doncaster, a corrupt moneylender).

According to Rumpole's creator, author John Mortimer, McKern "not only played the character Rumpole—he added to it, brightened it and brought it fully to life.

The move was part of a broader shift in their TV commercials, including hiring Dinah Sheridan to play McKern's wife.

Worried that his stout frame would not appeal to audiences, McKern suffered from stage fright, which became harder to control with age.

[15] McKern and his wife, fellow Australian actor Jane Holland (A Son Is Born, 1946), had two daughters, Abigail and Harriet.