See Oprah Winfrey in the Immortal Life of Henrietta Lacks trailer

Oprah Winfrey and Rose Byrne unearth buried history in the first trailer for The Immortal Life of Henrietta Lacks, HBO’s biopic about the black woman whose cells were harvested without her permission as she lay dying from cancer in 1951, paving the way for such medical breakthroughs as the polio vaccine, in vitro fertilization, and gene mapping.

Winfrey plays Lacks’ daughter Deborah; Byrne portrays Rebecca Skloot, the real-life journalist whose 2010 book inspired the telefilm; and Hamilton‘s Renée Elise Goldsberry plays Lacks in flashback.

As glimpsed in the trailer, Lacks’ family was kept in the dark about her contribution to medical science for many years, even as her cells helped treat countless people.

As Deborah Lacks tells Skloot in the trailer, “What you don’t understand is, we didn’t know nothing about nothing.”

The Immortal Life of Henrietta Lacks premieres April 22 at 8 p.m. ET on HBO. Watch the trailer above.