His other notable film performances include Golden Salamander (1950), The Clouded Yellow (1951), Mutiny on the Bounty (1962), The Charge of the Light Brigade (1968), Battle of Britain (1969), Lola (1969), Ryan's Daughter (1970), Superman (1978), Gandhi (1982), and White Mischief (1987).

Howard was born in Cliftonville, Kent, England the son of Mabel Grey (Wallace) and Arthur John Howard-Smith, an insurance agent.

[1] His father was an insurance underwriter for Lloyd's of London, serving as representative in Colombo, Ceylon and elsewhere; Trevor spent the first eight years of his life travelling around the world.

[citation needed] When he left school he worked regularly on stage, including in Sheridan's The Rivals, several performances at Stratford-upon-Avon, and in a two-year run in the original production of French Without Tears.

[11][12] Around 1945, journalists began to circulate stories stating that Howard had a courageous wartime service in the British Army's Royal Corps of Signals, which earned him much respect among fellow actors and fans.

[13] In fact, he "did his best to dodge the call-up",[14] and journalist Terrence Pettigrew, in his 2001 biography of Howard,[15] recounted that files held in the Public Record Office revealed he was actually discharged from the British Army in 1943 for mental instability and having a "psychopathic personality", on account of having "lied about his background, from his schooldays onward ...

[20] After a theatrical role in The Recruiting Officer (1943), Howard began working in films with an uncredited part The Way Ahead (1944), directed by Carol Reed.

Howard was in a French movie, The Lovers of Lisbon (1955), then supported Jose Ferrer in a war film from Warwick Pictures, The Cockleshell Heroes (1955), which was popular in Britain.

Howard starred in Manuela (1957) then supported William Holden in Carol Reed's The Key (1958), for which he received the Best Actor award from the British Academy of Film and Television Arts.

When William Holden dropped out of the lead of The Roots of Heaven (1958), Howard stepped in as his first opportunity at a starring role in a Hollywood film (although top billing still went to Errol Flynn).

He was in a TV movie production of Hedda Gabler (1962)[32] and played the title prime minister in "The Invincible Mr Disraeli" (1963), an episode of the Hallmark Hall of Fame for which he won an Emmy Award for his role then supported Robert Mitchum in Man in the Middle (1964) and Cary Grant in Father Goose (1964).

After a cameo in Operation Crossbow (1965), Howard supported Frank Sinatra in Von Ryan's Express (1965), Brando and Yul Brynner in Morituri (1965), and Rod Taylor in The Liquidator (1965).

He went back to military roles: The Charge of the Light Brigade (1968), as Lord Cardigan, and Battle of Britain (1969), as Air Vice Marshal Keith Park.

He made a Swedish film The Night Visitor (1971) then settled into a career as a character actor: To Catch a Spy (1971), supporting Kirk Douglas; Mary, Queen of Scots (1971), as Sir William Cecil; Kidnapped (1971); Pope Joan (1972); Ludwig (1972); The Offence (1972), with Sean Connery; A Doll's House (1973), for Joseph Losey; Who?

Howard appeared in some prestigious movies towards the end of his career: The Deadly Game (1982), The Missionary (1982), Gandhi (1982), George Washington (1984), Shaka Zulu (1986), Dust (1985), and Peter the Great (1986).

In an interview with Terence Pettigrew for his biography of Howard, Miles describes how she gave an ultimatum to the executives, threatening to quit the production if they got rid of him.

[4] A British government document leaked to the Sunday Times in 2003 showed that Howard was among almost 300 people to decline an official honour of the United Kingdom.