The actor Bernard Archard, who has died aged 91, established a forbidding presence as Lt Col Oreste Pinto, a character based on a real-life wartime counter-espionage interrogator, in the BBC television series Spycatcher (1959-61). Tall and angular, with receding hair and a prominent chin, he became a regular authority figure and inquisitor, though not in leading roles.   Archard was born in Fulham, London, where his parents were mayor and mayoress; his father was also a jeweller. He won a scholarship to Rada (1938-39), and an early stage role came as Orsino to Jessica Tandy’s Viola in Twelfth Night at the Regent’s Park open air theatre.

During the second world war, he was a conscientious objector, and was sent to work on land owned by the Quaker movement. At the Edinburgh Festival in 1948, in a production of the Glyndebourne Children’s Theatre, he met fellow actor James Belchamber, who was his partner for nearly 60 years.ore   Making his way around regional repertory, Archard worked at Chesterfield with Margaret Tyzack and at Sheffield with Paul Eddington, Peter Sallis and Patrick McGoohan; like many, he believed McGoohan to be a truly great actor, and they worked together again in a couple of episodes of McGoohan’s 1960s TV series Danger Man.   In the mid-1950s, Archard and Belchamber ran a touring repertory company, based in Torquay, with Hilda Braid among its players. They also collaborated on the book and lyrics for Our Jack, a musical based on Walter Greenwood’s The Cure For Love, in 1960.

Nevertheless, by 1959 Archard was thinking about emigrating to Canada with Belchamber. He postponed his trip to appear in a TV medical drama, then again to do Treason (1959), a Sunday-night play about the July 1944 plot to kill Hitler. Unknown to him, this rush of work resulted from a plan by writer-producer Elwyn Jones to demonstrate his suitability for Spycatcher.

Masterminded by Robert Barr, Spycatcher was also produced in the documentary manner, to the extent that Archard was not given billing in the Radio Times until some time into the run. Unlike later, action-orientated spy series, Pinto’s half-hour cases, sometimes little more than two-handers, were based on true stories. The debriefing of wartime refugees afforded many opportunities for Archard’s incisive qualities. One episode saw him get the desired answers from a suspect by throwing darts at a photo of Hitler.

Running for three seasons, the series brought Archard much recognition; he was wryly amused about receiving “two direct offers of marriage and about a dozen oblique ones”. Athough half of the episodes still exist, it has never been revived. Nonetheless, when on a continental tour of My Fair Lady in 1983, Archard’s presence in Amsterdam caused excitement – Pinto having been Dutch.

He was proud of his role as a magistrate in Terence Rattigan’s last play, Cause Celebre, in the West End in 1977, with Glynis Johns. Anthony Shaffer’s mocking The Case of the Oily Levantine, at the same venue, Her Majesty’s Theatre, two years later, was less successful. However, a full-scale theatrical disaster came with Peter O’Toole’s Macbeth at the Old Vic in 1980. Archard played Duncan; he had previously been Angus in Roman Polanski’s film version, in 1971.

In the film version of Dad’s Army (1971), Archard was a regular general dismissing Captain Mainwaring as a “damn bank clerk!” He was in several of the popular Edgar Wallace B-movies, as well as John Huston’s playful The List of Adrian Messenger (1963); he and Huston had a mutual friend in Deborah Kerr.

He was the Duke of Wellington in Number 10 (YTV, 1983), an anthology series depicting prime ministers. For publicity purposes, the actors who took the roles were photographed with Margaret Thatcher; Archard was not impressed by her, but then, he had been a lifelong reader of this paper. He also played a government figure in Hidden Agenda (1990), Ken Loach’s controversial film derived from the John Stalker inquiry.

After retiring in his early 80s, Archard lived contentedly in Somerset with Belchamber, who survives him.

· Bernard Joseph Archard, actor, born August 20 1916; died May 1 2008