[1] She trained as a dancer in Warsaw, and at the Imperial School in Petrograd.

[2] Pflanz danced with the Ballets Russes under Sergei Diaghilev,[3] touring in the company with Adolph Bolm, Léonide Massine, Xenia Makletzova, Valentina Kachouba, Tamara Karsavina, Enrico Cecchetti, and many others.

She appeared in productions of Khovanshchina (1913), Papillons (1914), Midas (1914), Prince Igor (1914), and La Légende de Joseph (1914) in Monte Carlo, Paris, and London.

[4] On tour with the Ballets Russes in the United States,[5] she danced in Prince Igor, Daphnis et Chloé, Nijinsky's Afternoon of a Faun (1916),[6] Till Eulenspiegel (1916),[7] and Cléopâtre (1917).

[9] Sophie Pflanz married Stanisław Burma-Dróbecki, Diaghilev's private secretary,[10] in London in 1911.