After getting an officer suspended from service, Ryu Su-yeol gets a step closer to a promotion. Oh Gyeong-tae looks for a young girl's missing mom.

Su-yeol searches high and low to prove Hui-gyeom's innocence. But the deeper he dives into the case, the closer he comes to falling into a trap.

Su-yeol reopens a closed case. He teams up with K to investigate quietly and uncovers the opponent's weakness. Meanwhile, the body count grows.