Along with several other middle-class, educated women writer contemporaries - Emilia Bernal, Lydia Cabrera, Ana Maria Simo, Hilda Perera Soto, and Rita Geada - Casuso left Cuba after the 1959 Revolution.

During her stay in Mexico in the 1940s, she appeared in a number of films as a supporting actress, including El tigre de Jalisco in 1947.

She participated actively in the student struggles against the dictatorship of Gerardo Machado and during Castro's exile in Mexico, helped in the preparation of the Granma expedition.

Upon her return to Cuba, she was appointed by the Commander-in-chief Fidel Castro as his Press Secretary and at the end of that year, Ambassador Extraordinary and Plenipotentiary Alternate Representative to the United Nations,[3] a position she held until her resignation and defection in October 1960.

[2] Casuso was married to Cuban writer Pablo de la Torriente Brau, who was killed fighting for the Republican side in the Spanish Civil War.