The Hwaseong serial murder case in Korea is very much like London’s Jack the Ripper — the cold case has gain so much cultural popularity for its gruesomeness that we have seen iterations of it in several kdramas’ police procedurals (like SignalGap-dong, to name a few).

And so here’s another one…

Main cast:

  • Choi Jin-hyuk (from Pride and Prejudice) as Detective Park Gwang-ho. He is the detective in charge of the Hwaseong cases back in the 80s, and travels by accident to 2016 — cos the serial murderer also time-travelled.
  • Yoon Hyun-min (from The Good Wife) as Detective Kim Sun-jae. An aloof detective who graduated from Police University but chooses to stay in field work. Gwang-ho is assigned to be his partner.
  • Lee Yoo-young as Psychologist Shin Jae-yi. A rather mysterious lady, she becomes the de facto profiler of the Serious Crime Unit 1.
  • Jo Hee-bong/ Kim Dong-yong as Jeon Sung-sik. In the 80s, he is Gwang-ho’s maknae partner, but in 2016, he has risen up the ranks to head Serious Crime Unit 1 (aka Gwang-ho’s boss).


We open to see a shadowy figure hits Gwang-ho on the head with a rock and the perp flees through a dark tunnel while Gwang-ho loses consciousness…

…flashback: Gwang-ho reluctantly accepts a blind date, and turns out to be rather smitten with his date, Yeon-sook (Lee Shi-ah). He eventually does marry her, even while busy trying to solve a series of cases where young ladies in their 20s-30s are strangled to death. The police teams go nowhere with their leads, even after interviewing dozens of suspects (and threatening several). Gwang-ho gets more desperate as the bodies pile up, and grieving family members question the efficiency of the police force.

By chance, he discovers that each body has a tiny dotted tattoo on the heel. The forensic doctor (or rather, he is juz a regular doctor being roped in to help with the postmortem) confirms the finding, but claims he did not report it earlier cos he felt it was “irrelevant”. The number of dots on the heel of the victims corresponds to the number of kills — but Victim 5 is missing (or her body is yet undiscovered).

Thinking that the first crime is likely where the murderer is hiding out, Gwang-ho sets out to investigate. He enters a tunnel and chases after a shadowy figure…and we are back to the opening…

…only this time, when Gwang-ho awakes and leaves the tunnel, he time travels to 2016. He goes back to his police station and has an altercation with Sun-jae, whom he thinks is a pastor from the nearby charity outfit (cos Sun-jae is in white shirt/ black pants…). Gradually though, Gwang-ho realises he is in a different space-time entirely.

Interestingly, another officer by the same name is supposed to be joining Serious Crime Unit 1…and that younger Gwang-ho somehow mysteriously disappeared with the arrival of the 80s’ Gwang-ho (even his pics poof into the 5th dimension). So Gwang-ho assumes the identity of this maknae, and doesn’t realise the team leader of Unit 1 is his maknae, Sung-sik, of the past. Sadly, Gwang-ho is unable to travel back in time, even after locating the correct tunnel and running through it back and forth several times. His pregnant wife, in the other time-space, is juz as devastated by the disappearance of her husband.

With no other choice, Gwang-ho has to hang around the 2016, and he meets profiler Jae-yi when one of his suspects, a female psychopath, commits suicide in the mental hospital. In Gwang-ho’s time, the female psycho was never indicted due to lack of evidence.

But Gwang-ho finally finds the reason why he is stuck in the 2016 when a call comes thru to the station on the finding of a dismembered body in the hills. The female body has 5 dotted tattoos on her heel.


Ep1 starts out rather slow, but it does build up enough background for viewers to understand the constraints of police work in the 80s. Besides the lack of advanced forensics, the police protocol then is kinda all over the place, and people turn a blind eye to co-erced confessions. Gwang-ho himself isn’t immune to using brute force to knock out confessions from his suspect, even though he isn’t a bad detective.

I’m also kinda interested Sun-jae…and his reason for hanging around in Unit 1 doing field work when as a graduate from the prestigious Police Uni, he could have easily gone upwards to management. Added to the fact that we know Yeon-seok was pregnant in the 80s, but nothing is known about her or her kid after that. Is Sun-jae Gwang-ho’s son? And the reason why he stayed on in field work is partly cos of his missing dad?

But what Tunnel does confirm is that the Hwaseong serial murderer time travelled, thus explaining why the murders mysteriously stopped in the 80s/90s. Luckily the detective tracing him has also entered the same time-space as him…