First published in 1963, Jakucho Setouchi's "Natsu no Owari (The End of Summer)" was the "Fifty Shades of Grey" of its day: a best-selling novel written by a woman that viewed the unconventional love life of its 38-year-old heroine with the sort of matter-of-factness then considered daring. But the story, based on the author's own experiences, was written with the plotless naturalism of the typical watakushi sho ̄setsu (I novel), while its impact came less from its heroine's sexual exploits and more from her absolute honesty.

Scriptwriter Takashi Ujita has included the book's most dramatic bits, while indulging in relatively little creative tinkering with its structure. This faithfulness extends to the film's period look, with Kumakiri and his staff venturing to Kakogawa in Hyogo Prefecture and Awajishima in the Inland Sea to capture the right Showa Era (1926-1989) atmosphere.

The film's biggest departure from the original novel is the casting of 27-year-old Hikari Mitsushima as the middle-aged heroine, Tomoko. An actress who has excelled at playing everything from a kick-ass cult member in the Sion Sono black comedy "Ai no Mukidashi (Love Exposure)" to the dying wife of an impoverished samurai in the Takashi Miike period drama "Ichimei (Hara-Kiri: Death of a Samurai)," Mitsushima gives exactly the performance the role calls for: emotionally transparent and complexly introspective. She inhabits Tomoko so naturally and vividly that we can read even her thoughts from moment to moment.