No one started, but everyone had it.

Joo-yong, a soldier serving his duty in the Korean army, attempts to expose the abuses from a senior soldier but fails. On that day, another violent situation happens by breaking a tooth of a second private soldier, and Joo-yong takes him to his brother in law's dental clinic.
While the brother in law reacts rather awkwardly towards his visit, Joo-yong is striken with a hunch that his sister has been being domestically abused. Joo-yong struggles to resolve the situations both within the platoon and his sister's home, he finds himself falling into violent actions himself.