The massive underground syndicate ‘Batalla’ has one absolute rule: once you enter, the only way out is in a body bag.Ryu Kang-min is one of their most lethal operatives, a shadow who has known nothing but blood and orders. But one day, the impossible is placed on the table—a special contract with "freedom" as the ultimate reward.The objective seems simple enough: travel to South Korea and eliminate a specific target. Eager to sever his ties to the underworld, Kang-min returns to his homeland. He casually slaughters a syndicate traitor just to warm up his trigger finger, proving he hasn't lost his edge. But getting to the real target won't be a straightforward hit. To complete the contract and earn his life back, this cold-blooded killer must infiltrate unfamiliar territory and do the unthinkable: enroll as a student. The warm-up is over. The real bloodbath is about to begin.