Bai's daughter was kidnapped a decade ago, leading Chen to vow catching the culprit. When Li's granddaughter faces a similar ordeal, Bai and Chen reunite, determined to bring the perpetrator to justice and unravel the haunting case.

BAI's daughter was kidnapped and died accidentally ten years ago, officer CHEN promised her to catch the criminal but retired without any result. Now LI's granddaughter was kidnapped and the modus operandi looks just same as the case ten years ago. BAI and CHEN reunite to investigate the case to catch the criminal.