"Black Knight" illustrates an air polluted world in 2071, where people depend on respirator masks to breathe. Only one percent of the human race has survived, and a strict social stratification has been established in the deserted lands of the Korean Peninsula. Delivery drivers play a crucial role within this system, and for refugees, becoming a delivery driver is their only hope for survival. Amid chaos, Black Knight tells the story of a legendary delivery driver 5-8 with exceptional battle skills and a refugee Sa-wol who dreams of following in his footsteps.