La Plante made her acting debut at age 15, and in 1923, she was named as one of that year's WAMPAS Baby Stars. During the 1920s, she appeared in more than 60 films. Her early films include Big Town Round-Up, with cowboy star Tom Mix, the serials Perils of the Yukon, Around the World in Eighteen Days, and several movies with Hoot Gibson. in an image published in the Exhibitors Herald The majority of the films starring LaPlante were made for Universal Pictures. During this period, she was the studio's most popular star, "an accomplishment duplicated only by Deanna Durbin years later", and almost always enjoyed top billing. One of LaPlante's early surviving films is the 1925 film Smouldering Fires, directed by Clarence Brown and costarring Pauline Frederick. Her best remembered film is arguably the silent classic The Cat and the Canary, although she also achieved acclaim for Skinner's Dress Suit, with Reginald Denny, the part-sound The Love Trap, directed by William Wyler, and the 1929 part-sound Show Boat, adapted from the novel of the same name by Edna Ferber. Although this last film was an adaptation of the novel, and not of the famous musical play also adapted from the 1926 novel, some songs from the play were included into the film as box-office insurance. She did not actually sing in the movie; her singing was dubbed by Eva Olivetti, one of the early instances in which this was done in a motion picture. A scene of La Plante in Show Boat was broadcast in the early days of British television.
The advent of sound films effectively shortened her career. In her mid-20s, La Plante was a natural and appealing presence in early sound films, but the huge wave of new stars in these years overshadowed her. She made her last appearances for Universal in the Technicolor musical King of Jazz. She appeared in God's Gift to Women, directed by Michael Curtiz and co-starring Frank Fay and Joan Blondell, and Arizona, co-starring alongside a young John Wayne.
Later career
La Plante subsequently went to Britain to work at Warner Brother's Teddington Studios. The company had faced criticism for the low quality of its "quota quickies", and her arrival coincided with an attempt to make more expensive productions. She starred in Man of the Moment, with Douglas Fairbanks, Jr. She appeared in the West End playing the lead in Ian Hay's Admirals All. La Plante briefly was considered to replace Myrna Loy in the Thin Man series when Loy thought about leaving, but Loy stayed as Nora Charles, and La Plante's career never rebounded. She retired from the screen in 1935, making only two later films, and 1957's Spring Reunion was her last. Her younger sister, actress Violet, never achieved Laura's level of fame; both sisters were WAMPAS Baby Stars. On June 3, 1954, La Plante made a guest appearance on Groucho Marx's quiz show You Bet Your Life. In this episode, La Plante discussed numerous topics, including her husband Irving Asher, who had just lost 25 pounds and completed the film Elephant Walk with Elizabeth Taylor. Mrs. Asher asked that her winnings, if any, go to the Motion Picture Relief Fund. They got three out of four questions correct to win $215. In the mid-1980s, a wheelchair-bound La Plante was brought on stage to wave to the crowd at the "Night of a Hundred Stars" event.
