Alla was born in 1929 into the family of a leading producer of Soviet cinema. In the midst of World War II her father, Oleksandr Horsky, was appointed director of the Kyiv Film Studio. Horsky's influence could have provided his daughter with a brilliant career and well-paid government contracts.

Alla chose a different path.

In the early 1960s, authorities allowed the Creative Youth Club "Contemporary" to be created in Kyiv. The goal was to show critics of the USSR that there were informal organizations in the country that were not controlled by the Communist Party. The Club held discussions, art evenings and exhibitions, they even copied forbidden books. In the open exchange of ideas between young artists, the style of Alla Horska was born, and it did not quite fit into the framework of the dominant "socialist realism." Her portfolio includes monumental art, paintings, drawings, and prints. The works were made in the tradition of the Kyiv Academic School of Folk Art, Ukrainian Avant-Garde and Boychukism (a school of Ukrainian art of 1910-1930s associated with the artist Mykhailo Boychuk).

All members of the Club, including Horska, were later called the "Sixtiers." They were not hostile to the Soviet Union, but they wanted change and truth. In 1962, eyewitnesses' accounts led Horska and her friends to Bykivnia, an area near Kyiv where Soviet punitive authorities shot 50,000 to 100,000 "enemies of the state" in 1937-1941, according to various estimates. They found a skull shot twice. Alla cried. "Imagine," she pointed towards the burials, "we are there... We could all be there…"

In 1964, Horska joined together with several like-minded artists and created a stained glass window "Shevchenko. Mother" in the lobby of the Kyiv University main building. It depicted Taras Shevchenko, Ukraine's major poet, as an indignant artist hugging a woman who was seen as a symbol of mother Ukraine. Above the composition was a quote from Shevchenko: "I will glorify those voiceless slaves! I will put a word on guard around them!" The stained glass work did not fit into Soviet ideological stereotypes, so it was destroyed.

In 1965, KGB took the members of the Creative Youth Club under surveillance. Horska's apartment was being monitored. Arrests soon began and yet, Alla was not afraid. She corresponded with political prisoners and provided moral and material assistance to their families. In 1968, Horska signed a "Letter of 139" in which representatives of Ukrainian intellectuals objected to authorities' repressions and secret trials of the dissidents. The result was the persecution of signatories and... rumors that a terrorist nationalist organization, which included Alla Horska, had appeared in Kyiv.

On November 28, 1970, Alla Horska went to her father-in-law in the town of Vasylkiv near Kyiv to get a sewing machine and did not return. A few days later, her body was found in the basement of the house of her husband's father, Ivan Zaretsky. The cause of death was listed as: "blows with a blunt object with a limited impact area," that is, with a hammer. Ivan Zaretsky was also found dead the next day. On November 29, his mutilated body was found on the railway track.

Horska's friends had no doubt that the murder was planned and carried out by intelligence agencies. The artist was a strong and outstanding opponent for them in times of humiliation and lies.

Alla Horska was not allowed to be buried in the center of Kyiv, so her last refuge was a suburban cemetery.