A fellow inmate at Bolingbroke County Poorhouse, Gabriel Blake, strikes up a unique friendship with Anne as she enters the home. An eccentric older prisoner, mild in nature, the other inmates and staff consider him a lunatic, causing him to be ostracized. He is mistreated and shunned by the others, having no one speak to him in years. Sharing a mutual love for writing and books with Anne, the two misfits develop a bond which others find difficult to understand.

They become each other’s only friends, much to the dismay of the Overseer and his wife. As the unlikely pair establish an increasingly deep connection, Gabriel leaves a definite mark in a young Anne’s life.