As a child, Kate Ashby (Michaela Coel) was rescued from the horrific aftermath of the Rwandan genocide. She was adopted and brought up in Britain by Eve Ashby (Harriet Walter), a world-class international lawyer. Kate has long struggled to escape the shadow of her past, but is now returning to work as a legal investigator in the same chambers as Eve, under leading international lawyer Michael Ennis (John Goodman). Kate and Eve’s relationship is strained to breaking point when a controversial militia leader, who had once fought to stop the genocide, is captured in the Democratic Republic of Congo, and Eve takes on his prosecution at the International Criminal Court.