Voice Season 4: Judgment Hour

A serial killer with enhanced hearing ability, identical to Kang Gwon Ju, appears and starts murdering people using it. Because of this, Kang Gwon Ju is driven into a corner, and she decides to cooperate with Detective Derek Jo to catch the serial killer. Derek Jo, a person of principle who doesn’t allow mistakes, is a team leader from the LAPD (Los Angeles Police Department), a team that deals with criminal gangs. Meanwhile, Gwon Ju has suffered from PTSD since the death of Do Gang WU, but she still carries out her duties as the leader of the emergency 112 call center.
(Source: AsianWiki)