Farr's first acting experience was in amateur productions with the Bedford Park Dramatics Club, in which her sister Henrietta and brother-in-law Henry were active members. Beginning in 1882, Farr served an eight-month apprenticeship under the actor-manager
J. L. Toole at the
Folly Theatre on King William IV Street near
Charing Cross, originally adopting the stage name of Mary Lester (in deference to her father's wishes, who did not want the Farr name associated with the theatre.) Her first professional stage appearance was as "Kate Renshaw", a schoolgirl, in
Henry J. Byron’s Uncle Dick’s Darling.
In 1883 her father died, leaving her a modest inheritance to live on. She continued taking minor roles at the Folly (including a performance two days after her father's death on 14 April), but changed her stage name back to Florence Farr when she began performing at the
Gaiety Theatre in May. With her commanding presence and beautiful speaking voice (noted by Shaw), she soon attained modest success on London's West End stages, and in 1884 she married fellow actor
Edward Emery. But it was a disastrous marriage, and she chafed under the restrictions expected of a
Victorian wife. In 1888, her husband left for an extended tour of
America, and they never saw each other again. (She eventually obtained a divorce in 1895 on the grounds of abandonment and never remarried.)
In early 1890 Farr moved in with her sister, Henrietta, and brother-in-law, painter and stage designer
Henry Marriott Paget, to
Bedford Park, a
bohemian London enclave of intellectuals, artists and writers. Bedford Park was known for its "free thinkers" and the "
New Woman" (a term coined by Shaw), where women participated in discussions on politics, art, literature and philosophy on an equal basis with men. An early
feminist, Farr was known for advocating equality for women in politics, employment, wages etc. amongst her intellectual circle of acquaintances. Yeats also lived in Bedford Park, and it's likely she first made his acquaintance when her brother-in-law was painting Yates' portrait.
While in Bedford Park, Farr starred in the play
A Sicilian Idyll: A Pastoral Play in Two Scenes by
John Todhunter (an associate of Yeats and fellow member of the Golden Dawn) in the part of "Priestess Amaryllis", who summons the Goddess
Selene to wreck revenge on her unfaithful lover. Shaw was in the audience to review the play, which he called "an hour's transparent Arcadian make-believe", but was greatly impressed with Farr's performance, as well as her "startling beauty, large expressive eyes, crescent eyebrows, and luminous smile."
Within a year Farr became Shaw's mistress, who wished to mold her into his idealized vision of "The New Woman" and be the star of his plays. Shaw wrote that she reacted vehemently against
Victorian sexual and domestic morality and was dauntless in publicly championing unpopular causes such as campaigning for the welfare of prostitutes. In a letter to Shaw she wrote, "…a race is likely to become degenerate so long as the sex question resolves itself ultimately into the question of how women can make the best bargain and, in so doing, deny themselves the liberty of free choice."
For Yeats she was, like
Maud Gonne, a poetic muse, who's resonate voice was perfect for reciting his poetry. He found in her "a tranquil beauty like that of
Demeter's image near the
British Museum reading-room door, and an incomparable sense of rhythm and a beautiful voice, the seeming natural expression of the image." In his review of
A Sicilian Idyll, Yeats wrote, "Mrs. Edward Emery (Florence Farr) …won universal praise with her striking beauty and subtle gesture and fine delivery of the verse. Indeed her acting was the feature of the whole performance that struck one most, after the verse itself. I do not know that I have any word too strong to express my admiration for its grace and power…I have never heard verse better spoken." Both men wrote leading parts in their plays for Farr, who used her influence with Annie Horniman to have them produced.
Farr was also the first woman in England to perform in
Ibsen's plays, in particular the role of "
Rebecca West" in the first English production of
Rosmersholm, at the Vaudeville Theatre in 1891, which gained her critical acclaim. The character of Rebecca West is a 'New Woman' who rejects the ethical systems of Victorian Era Christianity, which for Florence Farr was a virtual typecast role.