In 1950, a man named James Wright [Scott Adkins] breaks into Ito Dojo and confronts Sensei Shunsuke Ito [Kansuke Yokoi], asking about his father, Benjiro Ito.
A flashback to 1942, during the Battle of Bataan in World War II, follows Royal Air Force Wing Commander James Wright as he is shot down over the Philippines. He is captured by Japanese forces and taken to a brutal POW camp where Allied soldiers endure forced labor, hunger, and daily brutality under Lt. Col. Ito. Ito orders his right-hand man Captain Hirano [Shane Kosugi] to execute Wright, but Wright fights back, killing Hirano and two soldiers before escaping, only to be recaptured.
Inside the camp, officers organize underground fighting matches to entertain the guards. Wright is initially hesitant, but he is pushed to fight after seeing resisters executed. His prior martial arts training in Hong Kong gives him an edge; he defeats Koji, the camp’s top fighter, though his victories draw the ire of Ito and his enforcer Captain Endo [Masanori Mimoto]. Ito goes as far as to execute troops who fail to defeat Wright. His fascination grows as he realizes Wright’s techniques are forbidden, and he even seems to recognize the master who trained Wright.
As the fights escalate, Wright forms bonds with fellow prisoners, including American Captain Collins [Donald Cerrone] and Filipino sergeant Gabriel Villanueva [Michael Copon]. Theresa [Gabbi Garcia], a nurse compelled to work at the camp, provides medical aid and helps keep the group alive. Together, they hatch a plan to escape and pass along intelligence about Japanese troop movements to the outside.
James steals a radio from the camp and uses it to contact American reinforcements. Collins and Villanueva share the news that help is coming, and they decide to exploit an upcoming air raid to slip away. Ito grows more unsettled and brutal as the plan advances.
They slip outside to inspect a downed glider as a potential route, but Collins’s earlier action—killing a guard during the breakout—draws his own fate and leads to his execution later.
When Allied bombs begin to strike, James, Theresa, and Villanueva push their escape and, in a climactic confrontation, James defeats Ito. Ito stops his men from killing James out of respect for the martial artist’s skill, and James, Theresa, and Villanueva escape.
Back in the present, Shunsuke reveals that Ito has died years ago from illness and asks James to demonstrate his forbidden technique. James defeats Shunsuke, and Shunsuke returns Ito’s medallion, which Ito had stolen from James years ago.
