Li Yuan, a top weapons engineer, accidentally traveled through time in an experimental accident, and his soul attached to the body of a dying young scholar in the first year of Jingkang of the Song Dynasty. Faced with the turbulent dynasty and backward weapons and equipment, he relied on the vast knowledge of modern firearms in his mind and determined to use his own hands to create a protective force for this era.
Starting from the most basic gunpowder ratio and forging process, he explored step by step and overcame many difficulties. Taking advantage of the crude conditions, he improved firearms and created a powerful crossbow; he combined his metallurgical knowledge to try to improve the quality of steel; he even began to conceive of a more distant prototype of a "rifle" that belonged to this era.
His actions attracted the attention of the court, the jealousy of his colleagues, and the covetousness of his enemies. In the whirlpool of intrigues and in front of technological barriers, Li Yuan relied on his wisdom and courage to save himself from danger time and time again. Not only did he have to face the various constraints of ancient society, but he also had to fight against the invaders' cavalry.
He uses knowledge to change destiny and uses technology to shake history. In this strange era, he used a gun as a pen and gunpowder as ink to write a legend of his own - a technological fire ignited by a modern soul in ancient times, a magnificent epic about protection, innovation and resistance.
