Marrow slowly unfolds as a tale of grotesque cannibalism in a small village in the Balou Mountains of China's Henan Province. In the story, a mother takes extreme measures to provide her four mentally disabled children with a normal life. She feeds them a medicinal soup made from the bones of her dead husband when she finds out that bones 'the closer from kin the better' can cure their illness. When she runs out of her husband's bones, she resorts to a measure that only a mother can take.