In the quaint village of Rack-Armor Terrace, nestled at the foot of the Great Wall of China, the life of local peasant Ma Dasan takes an unexpected turn when he is confronted by a mysterious man known only as "Me". This stranger breaks into Ma's home in the dead of night, shocking him as he deposits two men wrapped in gunnysacks and orders him, at gunpoint, to keep them alive for interrogation over the next few days. One sack contains Kosaburo Hanaya, a combative Japanese sergeant, while the other holds Dong Hanchen, a sycophantic Chinese interpreter working for the Japanese military. Ma quickly realizes he must rally his fellow villagers to comply with the enigmatic "Me"'s demands, leading to the prisoners being hidden in Ma's cellar, away from the looming threat of their captor's return.
Amidst the tense atmosphere, Hanaya tries to provoke the villagers into killing him, but Dong, fearing for his own safety, cleverly manipulates what Hanaya says to make it sound more agreeable. As the Chinese New Year approaches without the promised return of "Me", the villagers' patience wears thin, and they resolve to execute the prisoners. When the luck of the draw places the task in Ma's hands, he grapples with his conscience and opts not to commit murder. Instead, he secretly relocates them to a watchtower along the Great Wall, visiting them to provide essentials. However, an ill-fated escape attempt by the prisoners exposes Ma's secret, resulting in heated arguments amongst the villagers. A decision is made to hire an assassin, prompting Ma to seek the help of a revered old executioner known as One Stroke Liu. Rumored to deliver deaths as painless as a breeze, Liu's attempts, however, fail spectacularly, leaving Ma in further turmoil.
As days pass, the once defiant Hanaya transforms, filled with gratitude toward the villagers and promising them grain in exchange for his release. Eventually, the villagers relent and return Hanaya to the Japanese forces, but the encounter doesn't unfold as they hoped. The Japanese Army, believing Hanaya to be a fallen war hero, reacts viciously to his return. The commanding officer, Captain Inokichi Sakatsuka, delivers a severe beating to Hanaya yet feels compelled to honor the grain deal. That evening, a festive feast is held in the village, with Captain Sakatsuka demanding the capture of the man responsible for Hanaya’s temporary imprisonment. When Ma, alongside his lover Yu'er, returns from a nearby town, they are devastated to find that the village is engulfed in flames due to Captain Sakatsuka's wrath.
In the aftermath, as the Chinese National Revolutionary Army reclaims the area, Dong finds himself publicly executed for his collaboration with the enemy, igniting a burning desire for revenge in Ma. Disguising himself as a cigarette vendor, Ma lurks outside the now POW camp, seizing an opportunity when Japanese soldiers approach. In a frenzied act of vengeance, he slaughters them and infiltrates the camp, igniting chaos. However, his rampage is short-lived as military guards apprehend him before he can reach Hanaya. Major Gao, overseeing the Chinese forces, condemns Ma's actions and orders a Japanese soldier to execute him before a gathering crowd. In a twisted turn of fate, Hanaya is forced to raise a katana against Ma, completing the cycle of violence as Ma's head rolls to the ground, performing the strange ritual of blinking and smiling, embodying the very fate foretold by One Stroke Liu.
