Attack Force Z

Five men are dispatched by submarine in Klepper canoes to rescue survivors of a downed plane on a Japanese-occupied island. They slip into the Straits of Sembaleng and prepare a covert operation. Led by Paul Kelly, an inexperienced commando officer, they plan to reach the crash site without alerting the enemy.

The team secretly lands on the island and hides their kayaks from enemy eyes. They move inland through the jungle, aiming to reach the crash site with minimal detection. The mission relies on stealth to avoid early confrontations.

As they advance inland, Ted 'Kingo' King is hit by fire from an unseen machine gun post. The team quickly eliminates the Japanese defenders and returns to their wounded comrade. The injury challenges the group's progress but reinforces the urgency of their mission.

King cannot be allowed to fall into enemy hands and jeopardize the operation. After sharing a cigarette with him, Costello shoots King to prevent interrogation and capture. The four remaining men press on with the search for the plane's survivors.

While scouring the area, the team encounters a rice farmer who tells them where the crash site lies. To preserve secrecy, the farmer is killed after sharing what he knows. The group continues the mission with renewed resolve.

A Japanese squad is spotted at a local house, but after they leave, the team enters the house and meets Lin, his daughter Chien Hua, and her younger brothers and sisters. The locals offer a tentative alliance and a guide toward the crash location.

With a guide, they proceed toward the plane but are attacked by Japanese soldiers at a Buddhist temple. The team is scattered in the chaos, and interpreter Jan Veitch ends up back at Lin's house to hide from the pursuing troops.

Japanese officers Watanabe and Imanaka torture Chien Hua to reveal the location of Lin and the survivors. Chien Hua refuses to betray them, maintaining loyalty under pressure. Veitch's presence adds tension as the search for the survivors intensifies.

Lin's son Shaw Hu falsely tells the Japanese that Lin, the Z men, and the plane survivors are heading for the island's capital. Veitch, with Shaw Hu's help, kills the two guards guarding the area to clear the path for the others.

During the fighting, Costello is wounded in the arm and cornered by a machine gunner. He throws a grenade to silence the weapon, but is shot and killed in the act. His sacrifice underscores the mission's high personal cost.

Locals blow up the wreckage of the downed plane to destroy evidence and aid the locals' stance. The team, now more cautious, questions villagers and learns the survivors may be being moved toward Lin's home. The search resumes with new urgency.

In the capital, Veitch guides the survivors toward safety, including the defecting official Imoguchi who possesses a secret that could end the war. Kelly realizes Imoguchi's rescue could be worth the risk and must persuade both his men and the local resistance to fight for it.