When Lin Wenxuan met He Changgui at a traditional Chinese courtyard house in Beijing, they barely got along.

Lin, an introverted intellectual from Taiwan, sought to buy the house or siheyuan, where He, the hot-headed stonecutter, lived. Their personalities clashed, coming in the way of the deal.

But as China fell to a full-scale Japanese invasion in 1937, the two men not only buried their personal differences but also got together to fight the war in their own ways.