Phyllis Thaxter: Actress who played the mother of Superman

Thaxter with Glenn Ford, as the adoptive parents of Superman in Richard Donner's 1978 film

With her warm personality and wistful voice, actress Phyllis Thaxter made an impact as the pregnant wife of a heroic airman in Thirty Seconds Over Tokyo (1944), and seemed set to become for MGM a more mature version of their wholesomely dewy-eyed star June Allyson in the 1940s, but that potential was never fulfilled, and she is best known now for having played Clark Kent's adoptive mother in Superman (1978).

Born in 1920 in Portland, Maine, Phyllis Thaxter was one of four children. Her father was a state supreme court justice and her mother was a Shakespearean actress and drama critic for the Portland Telegram.

On graduation from high school, Thaxter, determined to become an actress, and encouraged by her mother, joined the Montreal Repertory Theatre. In 1939 she went to New York and auditioned for a George Abbott comedy, What a Life. She won a small role, and understudied the star, Betty Field. Later Abbott suggested she try out for There Shall Be No Night starring Alfred Lunt and Lynn Fontanne. She was cast as the maid, and understudied the ingenue, as part of a company that included the bisexual actor Montgomery Clift, with whom Thaxter had a relationship. "We had a romantic two years," she recalled. "The Lunts were wonderful to us and I felt they hoped we would marry and become an acting team similar to theirs."

She played the title role in the Chicago company of the hit play Claudia, and took over the role on Broadway when Dorothy McGuire left to make the film version. She made her screen debut as the wife of war hero Captain Ted Lawson (Van Johnson) in Thirty Seconds Over Tokyo (1944), which told the true story of Lt Colonel Doolittle's air raid on Japan. She and Johnson conveyed a touching rapport and the film established Thaxter as the epitome of the clean-cut all-American sweetheart.

Next, she played a girl with a split personality trying to battle her evil self in an adaptation of Arch Oboler's radio play Alter Ego. Also during 1944, Thaxter ended her relationship with Clift and married James Aubrey, then an officer in the Army Air Corps but later a leading figure in the entertainment industry. The couple's daughter, Schyler Susan Aubrey, later became an actress as Skye Aubrey.

Thaxter had a small role in Week-End at the Waldorf (1944), and, after time off to have her daughter, she was cast as the teary daughter of Spencer Tracy and Katharine Hepburn in Sea of Grass (1947). In Living in a Big Way (1947) she was a war widow with three children. The leads, Gene Kelly and Marie McDonald, were constantly feuding and Thaxter recounted that Kelly asked MGM to alter the film's ending so that he would end up with her, but he was unsuccessful.

She was loaned to Columbia for Sign of the Ram (1948), then was teary again as the mother of a cloyingly angelic Margaret O'Brien in Tenth Avenue Angel (1948); the stark western Blood on the Moon (1948) provided one of her better roles. The same year she finished her MGM contract with the role of the faithful sweetheart of a former prisoner of war (Robert Ryan) in Act of Violence.

Thaxter then returned to Broadway in the Actors' Studio production Sundown Beach, directed by Elia Kazan, in a cast that included Julie Harris and Cloris Leachman. On screen she had a small role in No Man of Her Own (1950), based on a Cornell Woolrich story.

Then came what was arguably her finest screen role, in Michael Curtiz's The Breaking Point (1950), a superb version of Hemingway's To Have and Have Not which the writer himself regarded as the best of the film adaptations of his books. John Garfield played the impecunious owner of a charter fishing boat, with Thaxter providing a skilfully etched portrait of his loving but careworn wife.

Warners then gave her a contract, but though she was able to display some fire in the Randolph Scott western Fort Worth (1951), her roles were mostly unrewarding: understanding wife of athlete Burt Lancaster in Jim Thorpe – All American (1951), of alcoholic Gig Young in Come Fill the Cup (1951), of college professor Ronald Reagan in She's Working Her Way Through College (1952), and of a Union officer with southern sympathies (Gary Cooper) in Springfield Rifle (1952). The same year, during the filming of Operation Secret, she was stricken with a form of polio while swimming in the ocean in Maine. Pregnant at the time, she spent several weeks in an iron lung, but recovered to give birth to a son, James.

With her husband, who had become a TV executive, Thaxter moved to New York and appeared frequently on television. In 1962 she returned to Broadway as Art Carney's wife in the hit comedy Take Her, She's Mine. The same year, she and Aubrey were divorced (he would become president of CBS and later head of MGM), and she married Gilbert Lea, a publisher.

She returned to the screen as a New York matron in The World of Henry Orient (1964) but mostly worked in television for the next decade. Then in 1978 she made a surprising comeback. Her daughter married the executive Ilya Salkind, who was producing Superman, and he cast his mother-in-law and Glenn Ford as Martha and Jonathan Kent, the farmers on Earth who adopt the baby who would become Superman.

In the 1980s Thaxter returned to the theatre to appear in regional productions of such plays as The Little Foxes and The Gin Game. In 1985 she was one of three sisters in the television movie Three Sovereigns for Sarah, and in 1992 she was a regal matriarch in an episode of Murder She Wrote. For the last nine years she had suffered with Alzheimer's Disease.

Phyllis St Felix Thaxter, actress: born Portland, Maine 20 November 1920; married 1944 James T Aubrey (divorced 1962; one daughter, one son), 1962 Gilbert Lea (died 2008); died Orlando, Florida 14 August 2012.