British actress Nova Pilbeam and Derrick De Marney in the Hitchcock film “Young and Innocent” (1937). (Courtesy of MGM)

Once heralded as one of the most promising actresses of the 1930s — when she was in her teens — British star Nova Pilbeam made an impression in two early Alfred Hitchcock thrillers, “The Man Who Knew Too Much” and “Young and Innocent.”

She won critical admiration for her charm and naturalism in a handful of other movies and drew strong notices on the London stage as Peter Pan.

But her inability to make the leap to Hollywood and the unexpected death in 1941 of her first husband, a film director who was the great-grandson of the poet Alfred, Lord Tennyson, dimmed her appetite for movie fame. By 33, she made a determined exit from show business.

Ms. Pilbeam, who was 95 when she died on July 17 at her home in London, retained a certain mystique among film enthusiasts, mostly because of her association with Hitchcock on two of his formative thrillers. The cause was cancer, said a family friend, Andrew van der Beek.

“She was not a recluse but had an aversion to talking about her actress past and was known to deny being Nova Pilbeam if recognized in the street or at a restaurant,” he wrote in an e-mail.

Nova Margery Pilbeam was born in Wimbledon, England, on Nov. 15, 1919. Her father was an actor and theater manager. Ms. Pilbeam acted in amateur shows at age 5 and turned professional at age 12.

Her screen debut followed at age 14 in “Little Friend” (1934), as a child who watches her parents’ marriage disintegrate. It was a strong production, with a screenplay co-written by novelist Christopher Isherwood, and a chance for Ms. Pilbeam to display a precocious range of emotion and technique.

“There are times when she looks to be 40 and then, on the other hand, there are times in the play’s development when she looks to be 14,” Washington Post film critic Nelson B. Bell marveled. “With this obvious flexibility in the matter of years on her side, it is needless to say that Nova Pilbeam gives a completely comprehensive performance.”

The film made Ms. Pilbeam a bright new personality, but her curious name prompted the London Evening Standard to feature a contest for a better one. Readers waggishly suggested Beryl Beamstar and Nova Cinemata.

Time magazine reported that the actress, whose first name was an homage to her maternal grandmother from Nova Scotia, opted to keep her birth name, which she considered far less ridiculous than, say, Myrna Loy or Greta Garbo.

Ms. Pilbeam was under contract with Gaumont-British films, where Hitchcock was also working. He cast her in “The Man Who Knew Too Much” (1934) as the daughter of a British couple who stumble onto a political assassination plot. The chief villain, played by Peter Lorre in his English-language debut, kidnaps the child to silence her mother and father. (Hitchcock remade the picture in 1956 with James Stewart and Doris Day.)

Ms. Pilbeam, who professed a desire for more stage work, landed the role of Peter Pan at the London Palladium theater in 1935. A Times of London critic wrote that she has “the merit which in general distinguishes good Peters from bad: namely, that of taking the part seriously and distinguishing its particular swagger from the self-conscious mincing of a principal boy in pantomime.”

The next year, she starred as the doomed Lady Jane Grey — ensnared in royal court intrigue — in the much-heralded film “Tudor Rose” (1936), also known as “Nine Days a Queen.”

Hitchcock called on her services again for “Young and Innocent” (1937), playing a constable’s daughter who aids a young man falsely accused of murder (Derrick De Marney). They try to track down the killer, whose identity is revealed in a dazzling tracking shot at the finale.

Hitchcock was known for a dark prankish side that could unnerve some in the cast, and Ms. Pilbeam’s age did not immunize her. For a scene that took place in an abandoned mine shaft, she was made to dangle 15 feet above the ground, hanging in peril.

“I was terrified,” she told film scholar Brian McFarlane in 1990. “But Hitch had this quirky sense of humor, and he made the scene go on and on, so that I thought my arm would come out of my socket.”

Assistant director Penrose Tennyson held her arm during the sequence, and they married in 1939.

Around the time of her nuptials, Hollywood producer David O. Selznick summoned Hitchcock to Hollywood, and it was reported that Ms. Pilbeam was in the running to play the second Mrs. de Winter in Hitchcock’s version of Daphne du Maurier’s romantic thriller “Rebecca.”

But she told McFarlane that her name “meant nothing over there” and, instead, Joan Fontaine got the role and an Oscar nomination.

Ms. Pilbeam did not flounder in England. She was featured in “Cheer Boys Cheer” (1939), an Ealing comedy about two rival breweries, and she impressed film critics in the anti-fascism drama “Pastor Hall” (1940). But after Tennyson’s death in a plane crash in Scotland, she slowly withdrew from film work. “My first husband was in the profession, and had he not been killed, I might have stayed in it,” she told McFarlane.

She married in 1950 to Alexander Whyte, a BBC journalist who died in 1972. Survivors include their daughter, Sara.

Ms. Pilbeam spent her final decades cultivating her garden and refusing interview requests, for the most part. She became an unauthorized muse for Duncan Hannah, an American artist who painted images of her in the mold of his friend Andy Warhol.

“She was an iconic figure,” Hannah told the London Independent in 2007. “It was because she was obscure that I liked her. She belongs to me. She’s all mine.”