Edmonds was born in London, grew up in England. During World War II she was translator to General de Gaulle at Fighting France Headquarters in London, and after Liberation, in Paris. After this Penguin Books commissioned a series of translations from her. Tolstoy was her speciality.
Her translation of Anna Karenina, entitled Anna Karenin, appeared in 1954. In a two-volume edition, her translation of War and Peace was published in 1957.
She took the name Edmonds from her husband James Edmonds. They married in 1927.
The Australian critic Robert Dessaix thought Edmonds' version of Anna Karenina, though not entirely satisfactory, reproduced Tolstoy's voice more closely than that of Richard Pevear and Larissa Volokhonsky.