In 1940s apartheid South Africa, Milla de Wet discovers a child abandoned in the fields of her family farm. Ignoring the warnings of friends and family, Milla brings the girl, Agaat, into her home. But the kindness is fleeting, as Milla makes Agaat her maidservant and, later, a nanny for her son. At turns cruel and tender, this relationship between a wealthy white woman and her Black maidservant is constantly fraught and shaped by a rigid social order. Decades later, Milla is confined to her bed with ALS and is quickly losing her ability to communicate. Her family has fallen apart, her country is on the brink of change, and all she has left are her memories --- and a reckoning with the only person who remains by her side: Agaat.