Listen closely, because skilled voice profiler Kang Kwon Joo is back. Working tirelessly at the Emergency Call Center, she uses her first-rate hearing to save lives and catch culprits. When it comes to responding to emergencies within the vital “golden time,” Kang Kwon Joo is simply the best. Do Kang Woo is a mysterious man who’s able to tap into the mind of a criminal. He also hides a secret pain that he doesn’t share with anyone. When he meets Kang Kwon Joo, they reluctantly form a team. She can hear crime; he can think it. Together, they take on the most dangerous criminals their city has ever seen.