Episode 15 of My Perfect Stranger begins with us jumping back in time and following Yeon-woo, whom we now see is the one behind everything. He wrote all the matchbox notes too, he killed Beom-ryong and the other girls.
We then cut forward to Yeon-woo running down Hae-joon just outside the tunnel. He starts kicking his son, leaving Hae-joon a beaten mess. In fact, Yeon-woo even grabs a wood plank and beats him with that too.
Yoon-young realizes something’s amiss and on her way to Hae-joon’s, runs into Mi-sook at the entrance of the house. She points out that the culprit has been there – and finally unveils that the culprit is Yeon-woo. Alongside Detective Baek, the pair rush to the tunnel and save Hae-joon before Yeon-woo bashes him upside the head with a brick.
As a result of this, Yeon-woo is imprisoned and the Director’s residence is searched. Yoon is shocked that Hae-joon is in such a rough way, and he visits him in hospital. He’s unconscious but while he is, Baek and the others continue their search. They realize Yeon-woo has deceived everyone by lying about the dates he returned to town, given his passport stamps are for earlier dates. However, they don’t have any tangible evidence to go on just yet, so the investigation is at a bit of a stand-still.
Chung-a returns to town, holding a box full of letters that Yeon-woo wrote to her while she was in America. The handwriting is different from Yeon-woo’s everyday handwriting, and it seems he’s changed it specifically for Chung-a. This only made her like him more at the time, but when she saw the matchbox with the handwriting, she recognized it immediately and realized it was Yeon-woo. She didn’t say anything because she feared for her child’s wellbeing.
Hae-joon awakens in hospital and remembers moments involving his grandfather recognizing Yeon-woo’s handwriting and lashing out at his grandson while he was little. Hae-joon scrambles out the hospital and rushes to see him.
When he arrives, Yoon happens to be outside burning all the letters, deciding that they need to cover up all the evidence and just put everything behind them. Hae-joon is shocked that his grandfather would do this, and goes on to point out how awful his life will be in the future following this. Yoon collapses on the ground, weeping, while Hae-joon takes the final letter and rushes off to the station to drop it off.
This works to incriminate Yeon-woo, who’s imprisoned, as the attention turns to Hae-joon and Yoon-young, as the pair debate when to leave and head back home. Hae-joon tells his friend to say her goodbyes, and she heads to the music store with Yoon-young, deciding to use her money to buy a guitar for Hae-seob.
Yoon-young tells Hae-seob to be good to Soon-ae and do everything he can to stay with her. Yoon-young’s goodbye is one tinged with sadness, but it does give some good closure for the pair, as Yoon-young forgives her father and wishes him a happy life – a better life – going forward.
At the station, Hae-joon questions Yeon-woo over the murders and his motive. It turns out Yeon-woo actually found Hae-joon’s office, including everything about the murders and all the various documents too. He smashed the glass to get in and even found the manual for the time travel car too.
Hae-joon questions Yeon-woo’s feelings toward Chung-a, and he admits that he loved her. His real issues though stem from his mother, who never gave him a warm look and abandoned him when he was 7. This pushed him over the edge and explains why he wanted to murder people. He was triggered by anyone well read as it reminded him of her mother. It’s also why he gravitated to Chung-a too, as she was an orphan and wanted a family.
Hae-joon points out what a relief it is that his mum can escape Yeon-woo, as he suddenly realizes that Hae-joon is actually his son. Yeon-woo is shocked, as Hae-joon talks about how pathetic he is, and how he gets by on his victim mentality when he’s really just a cold-blooded killer. Just before he leaves, Hae-joon hands over a photo from their past, confirming their bond together.
Yoon-young also gets some closure with her mother, saying goodbye to Soon-ae and pointing out that she’s so happy that they met and spent time together. After finally saying their goodbyes, the pair prepare to leave. They set the timer for 2021, drive through the tunnel, and end up… stuck in 1987.
For a minute there, it seemed like the pair were going to end up in the future and find out that everything is completely different. How much has Korea changed since the pair have stopped Yeon-woo? I guess we’ll have to wait to find out because for now, it seems the pair are stuck in this time.
It may well be a simple case of fixing the car, but then that also delays the goodbyes, so I’m sure there must be another twist because we’ve got some niggling plot issues still to be resolved. Why did Yoo-seob react that way to the news? Why did Mi-sook keep the truth from everyone for so long? What is she planning in the future?
The time travel aspect of this series has really been an afterthought in many ways, and while that does mean we get a more focused look at this 1987 timeline, it also feels like a missed opportunity not to see how these little changes have affected the present day.
Speaking of missed opportunities, Yeon-woo’s motivation for killing is a bit weak. He has “mummy issues” and while it does make sense for him to be the killer, given his connection to our main character and the time travel car, it’s also a bit disappointing too. We haven’t seen him interacting with any of the different victims, while the investigation largely counted for nothing up until this point given what we know about Yeon-woo. And on that same note, why did he kill Yoon-young’s mother in the present? Why not go after Mi-sook too if he’s really going for “women who read”?
But then is there a final twist to come? It seems that there might be, given we have Min-soo, Mi-sook and Yoo-seob who have unresolved arcs that need to be cleared up. Failing that, it seems we could end up with another K-drama that ends in a rather disappointing manner. Let’s hope that’s not the case!