Watch online: Red Cliff: Battle of the World - 1024 resolution "Red Cliff: Battle of the World" BD with Chinese and English subtitles

The story takes place in the thirteenth year of Jian'an during the late Eastern Han Dynasty (AD 208), exactly 1800 years ago. Though Emperor Xian of Han, Liu Xie, was the nominal ruler at the time, the person who truly held power was Chancellor Cao Cao. He coerced Emperor Xian into declaring war on Liu Bei and Sun Quan in the south. Cao Cao claimed that his purpose in wiping out Sun and Liu was to unify the land under the Han dynasty, but in reality, he intended to depose Emperor Xian and proclaim himself as emperor. Leading an army of nearly a million soldiers to the south, Cao Cao's first target was Liu Bei, stationed in Xinye.

Upon arriving at Xinye, Cao Cao’s army quickly overwhelmed Liu Bei's forces with their overwhelming numerical superiority. Forced to flee from Xinye, Liu Bei retreated with his generals Guan Yu and Zhang Fei covering the rear to protect the retreating civilians. Meanwhile, General Zhao Yun, holding Liu Bei's infant son A Dou, fought valiantly through the enemy ranks, killing countless foes before finally breaking through the encirclement.

At this point, the defeated Liu army regrouped at Xiakou, separated from Cao Cao's forces only by the Yangtze River. Liu Bei realized that relying solely on the natural barrier of the Yangtze would not be a long-term strategy against the formidable Cao Cao army. Eventually, Cao Cao would cross the river, leading to the suffering of countless civilians. In a hurry, Liu Bei sent his strategist Zhuge Liang to Eastern Wu to negotiate an alliance with Sun Quan.

Eastern Wu, though well-equipped with troops and supplies, hesitated between surrendering and fighting against the formidable force led by Cao Cao. At the age of 26, Sun Quan and his ministers were undecided. Lu Su, one of Sun Quan's advisors, privately told Zhuge Liang that to convince Sun Quan to ally with Liu Bei against Cao Cao, they must first win over Sun Quan's military commander, Zhou Yu. Zhuge Liang traveled to Chibi to meet Zhou Yu, who was training Eastern Wu's elite navy. Zhuge Liang and Zhou Yu immediately hit it off; while enjoying playing the qin together, they discussed military strategies. There, Zhuge Liang also met Zhou Yu's wife, Xiao Qiao, known as the most beautiful woman in the world. Xiao Qiao's father had been an old acquaintance of Cao Cao.

Zhou Yu and Zhuge Liang jointly convinced Sun Quan to form an alliance with Liu Bei to resist Cao Cao. At this time, Cao Cao sent emissaries with a declaration of war, urging Sun Quan to surrender, which Sun Quan firmly rejected.

Enraged, Cao Cao dispatched General Xiahou Yuan to lead a cavalry unit to launch a surprise attack on the allied forces of Sun and Liu. However, Zhou Yu and Zhuge Liang were prepared. Ordered to fight back, Sun Quan's younger sister, Sun Shangxiang, who dressed as a boy, engaged Xiahou Yuan. Unaware of the ambush, Xiahou Yuan chased after her and fell right into the allied forces' trap. Xiahou Yuan fled in defeat, while his men surrendered en masse. During the battle, Zhou Yu saved Zhao Yun's life but was injured himself.

With the initial victory, the morale of Eastern Wu soared, and they set up camp at Chibi, where the terrain was perilous along the southern bank of the Yangtze River. On the opposite bank at Wulin, Cao Cao established a stronghold, deploying over two thousand warships for his navy. To deceive the enemy, Cao Cao secretly intensified his preparations for war while having his troops play "cuju," an ancient Chinese football game.

Sun Shangxiang, brave and skilled in combat, disguised herself as a man and infiltrated Cao Cao's camp to gather intelligence. There, she met a Cao general named Sun Shucai, with whom she eventually developed feelings. Sun Shucai...