Shinnosuke is introduced to Shizu as a prospective marriage partner, but he falls in love with her widowed sister Oyu. Convention forbids Oyu to marry because she has to raise her son as the head of her husband's family. Oyu convinces Shinnosuke and Shizu to marry so that she can remain close to Shinnosuke.
An intellectual couple in a staid and tedious marriage are surprised when the wife’s niece, who has run away from home, turns up unexpectedly to stay with them. Their mundane lives are sent into disarray by the emotional and energetic Ako.
