Antony Sher, a South African-born actor who brought empathy, intelligence and scorching intensity to his performances on the London stage, playing roles as varied as a torch singer, Holocaust survivor and psychopathic king, died Dec. 2 at his home in Stratford-upon-Avon, England. He was 72.

His death was announced by the Royal Shakespeare Company, which said he had cancer. His husband and only immediate survivor, Gregory Doran, the RSC’s artistic director, had gone on leave in September to care for him.

Diminutive and mild-mannered, Mr. Sher had a chameleonlike ability to disappear into roles. He used makeup and prosthetics to transform himself into rogues, misfits and other outsiders, and he acknowledged trying to undergo a similar metamorphosis as a young man when he moved to England in the late 1960s to study acting.

Embarrassed by his identity as a gay Jewish South African, he said he tried “to act like a proper Englishman,” dropping his accent and pretending that he was a straight gentile from London. “I cornered the market in minorities,” he told Britain’s Independent newspaper. “I didn’t want to be any of these things, but by being an actor you could pursue other identities.”

With a carefully modulated voice and a face that seemed as malleable as clay, he appeared in plays by 20th-century giants such as Harold Pinter and Sam Shepard, and he seemed to draw on those works while breathing new life into the classics. A member of the Royal Shakespeare Company since 1982, he was considered one of his generation’s foremost interpreters of Shakespeare. Former company director Terry Hands once likened him to “a blowtorch without a handle,” saying, “He lives, eats, sleeps whatever play he is in.”

Mr. Sher delivered his breakthrough performance in 1984, starring in “Richard III” as the play’s hunchbacked title character. In a departure from previous Richards — notably the dry-humored villain portrayed on film by Laurence Olivier — he interpreted the role as a sprightly, crutch-wielding madman, the embodiment of evil.

“Pivoting across the stage on spindly black crutches, looking more a black widow spider than a king, he initiated a whole new wave of Shakespearean acting,” Jonathan Myerson wrote in the Independent in 2004. “His Crookback required such feats of strength and pain-endurance and osteopathy that everyone else just had to emulate it. From now on agony and acrobatics were going to be par for the course if audiences were going to be impressed.”

Mr. Sher was jointly honored for Richard and his next role, as the kvetching drag queen in Harvey Fierstein’s “Torch Song Trilogy,” with the 1985 Olivier Award for actor of the year. He received the acting prize again in 1997, after playing the title character in Pam Gems’s “Stanley,” an exploration of painter Stanley Spencer’s tempestuous life and art. The play moved to Broadway later that year, and Mr. Sher received a Tony nomination.

As Spencer, he painted and drew onstage, mimicking the artist’s style and calling on his own youthful training as a painter. He had shown an aptitude for art as a boy, but after his parents enrolled him in elocution classes as a remedy for shyness, he discovered the joy of “hiding away in public,” as he put it, “instead of in a solitary room or in a studio.”

Mr. Sher said he saw acting as an extension of portraiture, and he filled the margins of his scripts with drawings that he used to sketch out the look and mannerisms of his characters. After finishing a theatrical run, he often painted himself in the role. “The artist in me always taunts the actor for falling short,” he wrote in “Characters” (1989), a collection of his sketches and paintings.

He broadened his artistic interests further by writing novels, plays and memoirs, beginning with “Year of the King” (1985), an account of his transformation into Richard III. His autobiography, “Beside Myself,” (2001) was an unsparing exploration of his upbringing and insecurities, and revealed that he had struggled with cocaine addiction.

“I don’t think that all creativity stems from suffering and conflict, but that’s certainly my experience,” he told the Guardian after the book’s release. Still, he said, he had also come to terms with his own identity, and — perhaps as a result — had moved toward a more internalized style of acting, focusing less on transforming himself physically than on revealing a glimpse of his character’s soul.

“You can’t be a good actor,” he once said, “unless you start playing from within yourself.”

Antony Sher was born in Cape Town on June 14, 1949, and grew up in suburban Sea Point. His Jewish grandparents had traveled to South Africa from Lithuania, fleeing the pogroms in a journey that Mr. Sher fictionalized in his best-selling first novel, “Middlepost” (1988).

Mr. Sher said that his father was a hard-drinking, emotionally distant businessman who exported animal hides. His mother was a homemaker who believed that he was born for greatness. After he was knighted in 2000, she told him that he should have been made a lord.

Moving to England at 19 was a bracing experience. He ended up burning his South African passport and volunteering with anti-apartheid organizations, and he found that it was generally more difficult to be Jewish and gay — homosexuality was partly criminalized at the time — than it had been in his home country.

After studying in London at the Webber Douglas Academy of Dramatic Art, Mr. Sher made his West End debut in 1974, donning a false nose to play Ringo Starr in the Beatles musical “John, Paul, George, Ringo . . . and Bert.”

He later starred as a police officer investigating a murder in “A Prayer for My Daughter” (1978), with Donal McCann at the Royal Court Theatre; as a Hollywood screenwriter in the Royal National Theatre’s production of Shepard’s “True West” (1981); and as a lecherous college professor in “The History Man” (1981), a BBC TV series adapted from Malcolm Bradbury’s novel.

Mr. Sher had a brief first marriage before he came out in 1989, inspired by the example provided by actors Ian McKellen and Simon Callow. Around that same time, he started a relationship with Doran, who first directed him in the RSC’s 1987 production of “The Merchant of Venice.” They entered into a civil partnership in 2005 and married a decade later, after same-sex marriage was legalized.

Although Mr. Sher was known for the explosive energy that he brought to roles, he could also dazzle in quieter parts, notably as the Italian author, chemist and Holocaust survivor Primo Levi. He played Levi in a one-man stage show, “Primo,” that he adapted from Levi’s memoir, “If This Is a Man.”

Rather than try to re-create the Holocaust onstage, he portrayed Levi in his reflective middle years, looking back on the horrors of Auschwitz with restrained precision. The show was filmed for a TV movie that aired on HBO and the BBC, and Mr. Sher received a Drama Desk Award for acting after it came to Broadway in 2005.

On-screen, Mr. Sher had supporting roles in Terry Jones’s fantasy movies “Erik the Viking” (1989) and “The Wind in the Willows” (1996), and he starred as a chortling Prime Minister Benjamin Disraeli in the historical drama “Mrs. Brown” (1997), with Judi Dench. He also played the bard’s shrink in “Shakespeare in Love” (1998).

For the most part, he stuck to the stage and aged into classic roles as one of the RSC’s stalwart members. He starred as Willy Loman in a 2015 production of “Death of a Salesman” and played King Lear the next year, in a production that came to the Brooklyn Academy of Music in 2018.

In his last role for the company, he appeared opposite playwright John Kani in the two-hander “Kunene and the King” (2019), an examination of apartheid’s legacy. Mr. Sher played a terminally ill South African actor preparing for the role of King Lear.

“As an actor, I’m not interested in bringing the role to myself and just ‘putting it on,’ ” he told the New York Times in 1997. “I’m interested in investing my work with my own emotional recall, my own heart. That’s the kind of acting that thrills me.”

Correction: An earlier version of this obituary incorrectly referred to laws surrounding homosexuality in Britain. When Mr. Sher came to England in 1968, homosexuality was partly but not entirely criminalized. The Sexual Offences Act of 1967 had partially legalized same-sex acts between men over 21. The article has been corrected.