Natalia Osipova Trades Pointe Shoes for a Play Script in London

Natalia Osipova, a principal at the Royal Ballet since 2013, is performing eight shows a week at the Theater Royal Haymarket — not dancing, but acting. Since "The Standard of Living," a new play by James Graham, opened in late September, one of ballet's biggest names has been playing Lydia Lopokova, the Russian ballerina who married the economist Maynard Keynes, opposite Rory Kinnear.

The turn began with an injury. In June, at the end of the Royal Ballet season, a hip problem forced Osipova out of the company's summer tour to Japan. It also cost her a planned run of "Don Quixote" — a signature role — with American Ballet Theater.

"I was like, 'No! I am dancer!'" Osipova, 40, said in her dressing room at the Theater Royal Haymarket last week, recalling her first reaction to the offer.

The offer came through her friend, the former Royal Ballet principal Edward Watson, who relayed a question from the theater director Nicholas Hytner: would she play Lopokova in the new play by Graham, the writer behind "Ink" and "Dear England"?

Her resistance did not last long.

"Then I thought: I like acting, I am interested in character," she said. "I will just try it, and I'm not going to get upset if it's no good."

What does the stage transfer change for Osipova?

By her own account, the skills overlap more than her first reaction suggested. Her verdict on the switch amounts to a working hypothesis: same discipline, different instrument. She approaches the part as she would a role in the ballet repertory — through character.

The results, so far, are measurable in one currency that matters in the theater: reviews. Osipova has earned mostly admiring notices for her portrayal of Lopokova since the production opened in late September.

The subject of the play gives the casting its own logic. Lopokova was herself a Russian ballerina who crossed into a different world — she entranced Keynes, who was enthusiastically gay, after he saw her perform in Diaghilev's Ballets Russes production of "Sleeping Beauty." A ballerina playing a ballerina who stepped outside ballet is a tidy symmetry, and one the production clearly counted on.

What remains unsaid is how long the experiment lasts. The hip injury that cleared Osipova's calendar will heal; the Royal Ballet's season will resume; "Don Quixote" remains hers to dance. Eight performances a week in the West End and a principal's schedule at Covent Garden do not obviously fit in the same diary.

For now, the answer is running on stage at the Haymarket, with Kinnear as Keynes, in a play that asks what a standard of living actually is — a question its lead actress is answering, one show at a time, from the other side of the footlights.