Her name was Henrietta Lacks, but scientists know her as HeLa. She was a poor black tobacco farmer who worked the same land as her slave ancestors, yet her cells - taken without her knowledge - become one of the most important tools in modern medicine.

Taken in 1951, these cells became the first immortal human cell line ever grown in culture. They were vital for developing the polio vaccine; uncovered the secrets of cancer, viruses and the effects of the atom bomb; helped lead to important advances like in vitro fertilisation, cloning, and gene mapping, and have been bought and sold by the billions. Put together, her cells would now weigh more than 22 million tons and placed end-to-end would wrap around the earth five times. Yet Henrietta's family did not learn of her 'immortality' until more than twenty years after her death, with devastating consequences ...

Now Rebecca Skloot takes us on an extraordinary journey, from the 'coloured' wards of Johns Hopkins in the 1950s to poverty stricken tenements of East Baltimore today, where Henrietta's children are unable to afford health insurance, and struggle with feelings of pride, fear and betrayal. Their story is inextricably linked to the birth of bioethics, the rise of multi-billion dollar biotech industry, and the legal battles that determine if we own our bodies.