Black Belt, known as Kuro-obi (黒帯) in Japan, is a 2007 Japanese martial arts drama film directed by Shunichi Nagasaki.
Taikan (Tatsuya Naka 7th Dan JKA Shotokan karate), one of the top students, challenges the leader of the detachment, Captain Tanihara.
Another senior student, Choei (Yuji Suzuki, 1st Dan Kyokushin karate), tries to stop this, thus causing one of the soldiers to slash his arm with a sword, permanently disabling him.
After Taikan and Giryu (Akihito Yagi 7th Dan Meibukan Gōjū-ryū karate) drive the soldiers out in a series of duels, the master Eiken Shibahara (Yosuke Natsuki) (whose dojo is located on the southernmost Japanese island of Kyushu) dies before passing on the Kuroobi (black belt) to his successor.
Giryu is stabbed near the stomach, and fell off of a cliff, unconscious, and was rescued afterwards by a boy named Kenta, and aided by his elder sister, Hana, and father, Kenkichi.
Giryu finds the gang's hideout, he initially gains the upperhand, but is forced to stop after one of the gangsters managed to capture Kenta.