Korean sales company Indiestory has announced that sleeper hit documentary Old Partner is due to open in Japan this December.

Japanese production and exhibition company Siglo picked up the rights earlier this year (outside of any film market event), and is planning a limited release on three prints in the busy Tokyo neighborhoods of Shibuya, Ginza and Shinjuku.

Old Partner also sold to Schalo Media for the US. The company previously distributed Crossing, which was South Korea’s selection for the best foreign-language film category of the 2009 Oscars.

Directed by Lee Choung-ryoul in HD, the ultra-low-budget documentary follows the travails of an old and ailing farmer and his old partner of several decades, a faithful cow.

The film became an unexpected hit on its local release at the beginning of this year, clocking up $15m and around three million admissions. It ranked seventh in the first half of the year’s Top Ten, beating John Woo’s Red Cliff 2 which was released a week later than Old Partner, on Jan 22.

The film debuted at the Sundance film festival and picked up awards at festivals including Hot Docs and Silverdocs.

At the recently-wrapped Asian Film Market in Pusan, Indiestory also announced sales on Old Partner to Swallow Wing Films for Taiwan and One Dollar Productions for HK/China.