A Single Spark is based on the real life of Jeon Taeil, A manual worker who protests the current labour laws by declari ng his humanity through burning himself to death at the young age of 22. Kim Youngsoo, a law-school graduate is obsessed with the death of Jeon Taeil. In order to better understand Jeon, he re ads Jeon's diary given to him by Jeon's mother. He also interviews people who used to know Jeon during his short life as a manual worker. The more he learns about Jeon, the more he sees himself in the worker who committed suicide. Overlappi ng himself with Jeon becomes his sole reason to live. But in the same way that Jeon was obliged to sacrifice himself for the cause so Kim must also sacrifice himself in some way.