In 1888, she produced a stage adaptation of The Scarlet Letter at the Royalty Theatre, starring as Hester Prynne with Johnston Forbes-Robertson as Dimmesdale.

[2][7] Calhoun moved to Paris to study and appear on stage with the famous French actor Benoît-Constant Coquelin.

They starred in a French translation of The Taming of the Shrew at the Théâtre d'Orléans, with Calhoun playing Katherine.

He was born Eugen Czernucki in Zagreb, but family tradition claimed descent from Lazar of Serbia and Vladislav Hercegović, and he reinvented himself as the fourteenth Duke of St. Sava and heir to the Serbian throne.

The couple were prominent advocates for Serbia and co-wrote a book, The Servian people, their past glory and their destiny (1910).