Japanese “Pacific Rim” star Rinko Kikuchi will topline “Last Summer,” an English-language drama about a  Japanese woman trapped on a yacht with the child she is losing custody of.  High-profile Italian indie pic is being helmed by Italo multi hyphenate Leonardo Guerra Seragnoli and produced by Luigi Musini and Elda Ferri (“Life is Beautiful”).

The international cast also comprises “True Blood” thesp Lucy Griffiths, Denmark’s Yorick Van Wageningen (“The Girl with the Dragon Tatoo”), and Danish thesp Laura Sofia Bach. Casting director is Avy Kaufman.

Kikuchi will play the free-spirited but reckless Naomi  who has four days to spend with her six-year-old son Ken before she loses custody of him forever to a wealthy Westerner. Confined to her father-in-law’s yacht off the coast of  Otranto in Southern Italy, Naomi is treated more like a prisoner than a guest by the boat’s four-person crew as she tries to forge a long-lasting maternal bond.

This rare case of an Italian production with an entirely international cast is co-penned by best-selling Japanese author Banana Yoshimoto (“Kitchen”) and the Tokyo-based cult Italo graphic author known as Igort.

“Summer” will rep a feature film debut for Rome-born, U.S.-trained Leonardo Guerra Seragnoli whose shorts have scored nods and who is among executive producers on “Jack & Diane.” The film’s costume designer is Italian multiple Oscar winner Milena Canonero (“The Grand Budapest Hotel”).

“I think we’ve set up an unusual, interesting and ambitious Italian film with an entirely international cast shot in a beautiful local setting that is not well-known to foreigners,” Musini boasted.

He noted that having Kikuchi in the lead should make the pic appealing for Asian auds, especially in China where “Pacific Rim” did boffo biz, besides Japan, of course.

Kikuchi, who was Oscar-nommed in 2006 for her supporting role in “Babel,” will next star in Isabel Coixet’s “Nobody Wants the Night.”

“Summer,” which is currently in its third week of shooting, is being produced by Musini’s Cinema Undici and Elda Ferri’s Jean Vigo shingle with the helmer’s own Essentia company and RAI Cinema. Talks are in initial stages for an international sales company to board the pic and kick off sales in Berlin, the idea being for the pic to launch at a fest starting from Cannes onwards.