Nader's wife wants to leave Iran with him and their daughter Termeh. She has already arranged everything and is eager to start a new life abroad. Nader, however, has his reservations. He worries about his father, who has dementia, and does not want to leave him to his fate. Therefore, he decides that the family should stay at home. The dispute lands them in the family court.
His wife Simin disagrees and refuses to live with him any longer. She leaves for her mother, leaving Nader and Termeh alone. Nader has difficulty coping with this new situation and hires a young woman to look after his ailing father. Little does he know that the new carer is not only pregnant but also working without her husband's permission. Nader soon finds himself caught in a web of lies, manipulation and confrontations.
After winning several awards at the Berlin Film Festival, including Best Actor, Best Actress and Best Film, A Separation also won the Oscar as well as the Golden Globe for Best Foreign Film.