Henri's career got off to an early start when she joined Florence St. John's Opera Company at the age of 15, but she left that troupe to help start her husband's acting career. Together, they struggled to establish more secure careers in the theatre and eventually obtained steady employment in D'Oyly Carte touring companies. Henri was promoted to play the leading mezzo soprano roles in the Gilbert and Sullivan operas and the other productions of the company for about a decade. However, in 1898, after her husband became a principal player in the main company at the Savoy Theatre, Henri retired from the stage at the age of 34.
Henri left the Drury Lane to join the D'Oyly Carte Opera Company to play the small role of Ada in the first provincial tour of Gilbert and Sullivan's Princess Ida, beginning in February 1884, in which Courtice Pounds played Hilarion and Fred Billington played Hildebrand. She obtained an audition for Lytton, claiming that he was her brother, and he was also engaged in the chorus and small parts, and immediately as the understudy for the role of King Gama in Princess Ida. The Ida tour continued for almost a year, and then the couple toured in additional D'Oyly Carte productions, interspersed with other engagements until May 1885. Also, in January 1885, Henri gave birth to the couple's first child, Ida Louise Jones, taking off only a few weeks before returning to the stage.
In the summer of 1885, she and Lytton joined with other out-of-work actors and travelled from town to town in Surrey for three months, performing a drama called All of Her, a comedy entitled Masters and Servants, and an operetta, Tom Tug the Waterman. The plays were augmented by songs and dances. The income provided by this work was not adequate, and the struggling young actors experienced hunger. In the fall of 1885, Henri and Lytton joined a D'Oyly Carte tour, playing in Trial by Jury (with Henri as the First Bridesmaid), The Sorcerer, Patience and The Pirates of Penzance. The two then played in the Christmas pantomime of Cinderella at the Theatre Royal, Manchester.
In 1886, they joined the chorus of Erminie, starring Florence St. John, and The Lily of Leoville by Ivan Caryll and Clement Scott, at the Comedy Theatre, and then toured in Erminie into the fall of that year. Whenever out of work, Lytton took more odd jobs, putting his artist training to use part of the time by painting decorative plaques. At the end of the year, Lytton was engaged in the chorus of The Mikado, which was nearing the end of its original run at the Savoy Theatre. Not only did Henri help Lytton get started in the theatre world and nurture his career, but Lytton was nearly musically illiterate, and Henri played the piano for him to prepare him for his roles, as well as coaching him in acting.
Lytton became understudy to George Grossmith at the Savoy Theatre in January 1887 for the original production of Ruddigore, and when Grossmith fell ill, he had a chance to play the central character, Robin Oakapple. This led to an engagement for Lytton to play the principal comedian roles with D'Oyly Carte touring companies, beginning in 1887. In 1888, Henri joined him on tour, when she first played Edith in The Pirates of Penzance, Pitti-Sing in The Mikado, and substituted in April as Josephine in H.M.S. Pinafore. By November 1888, however, Louie went on maternity leave.
In 1896-97, Henri toured as Julia Jellicoe in The Grand Duke, as well as Nekaya, Constance Partlett in The Sorcerer, Cousin Hebe in Pinafore, Edith, Lady Angela in Patience, Iolanthe, Melissa, Pitti-Sing, Phoebe, and Tessa. In June 1897, she was called to the Savoy Theatre, joining Lytton there, where she was a chorister in the revival of Yeomen and the new production of The Grand Duchess of Gerolstein, while creating the title role in Old Sarah, the companion piece to both works. In March 1898, she played Tessa at the Savoy in the first revival of The Gondoliers.
Henri left D'Oyly Carte and retired from the stage in May 1898. Lytton claimed, in his 1922 memoir, The Secrets of a Savoyard, that she also appeared at some point in her career as the Plaintiff in Trial by Jury and Mrs. Partlett in The Sorcerer, which he says was "probably ...a greater number of parts... than any other lady connected with the company. Lytton died in 1935, and Henri survived him by a dozen years.
Henri died in Surbiton, Surrey at the age of 83, survived by her son Henry Lytton, Jr., whose high profile marriage to Jessie Matthews in 1925 ended in divorce in 1930. The couple also had two other sons, one of whom was a pilot killed in World War I, and a daughter, Ena Elverstone. They also had two other children who died in infancy.
Years later, Henri appeared in several silent films, perhaps the best knows of which was the 1913 film Sixty Years a Queen, in which she played Queen Victoria.