Born in 1930, Hoa was from a southern upper-class family, which had been Frenchified during the colonial era. After completing her secondary schooling in Vietnam, she moved to Paris in the 1950s, where she became a communist. Upon finishing her degree, she returned to southern Vietnam, which following the partition of Vietnam following the Battle of Dien Bien Phu and the Geneva Conference had become part of the anti-communist Republic of Vietnam. During this period of the late 1950s and early 1960s, Hoa spied for the communists, as she socialised with the Saigon elite at cocktail parties with the inner circle of President Ngo Dinh Diem and the American advisors in Vietnam, who were oblivious to the fact that the upper-class southerner was a communist.