7 Theories That Make 'When The Phone Rings' The Best K-Drama Of 2024

Netflix K-drama When The Phone Rings is the one thing on the minds of most K-drama fans right now. The wait for the weekend has never felt so long, and everybody is eager to see what’s happening next. Of course, some of us are just here to enjoy the chemistry between the two leads, which is sizzling, but the rest of us are stuck on who this kidnapper really is. There are many fan theories about who the bad guy is, but you have to keep in mind these are all from us viewers who haven’t read the Webtoon. The ending of episode 6 implies that someone in a black jacket pushed Hee-Joo off the cliff on purpose. This has sparked debates that Park Do-Jae, Sa-Eon’s trusted assistant, is the man we’re after. I’m going to be honest with you; I didn’t even know the man’s name until I saw these rumors floating around and had no idea what to make of them. But reading more into the theories, I can admit there might be some meat on the bone here; however, I feel like he’s a red herring. With that said, though, let’s jump into the many theories we have for When The Phone Rings.

Spoiler Alert

1. Who Is Sa-Eon?

In episodes 5-6 we learn that in the orphanage there was a pair of twins, and one of the boys disappeared along with a few other kids. We also know that Sang-Woo knew a “psychopathic/sociopathic” kid back in the day who lived in a mansion near the orphanage. The show then implies that the kid was kept locked up because he might’ve killed a cat and/or hurt the missing kids. But this “killer” kid could be Sa-Eon himself, so who is the person married to Hee-Joo, and why is he posing as Sa-Eon? Well, that’s because the real Sa-Eon comes from a powerful family that cannot be exposed as a psychopath breeder, so the theory is that the real Sa-Eon was replaced by one of the twins. Take, for example, when Sa-Eon’s mum says he liked seafood, but Sa-Eon nearly threw it all out (but gave it to Hee-Joo instead?). It seems like he also understands how she’s being treated as an outsider, maybe because he too is an outsider? 

2. Is The Kidnapper The Other Twin? 

Theory number 2 is that the kidnapper is Sa-Eon’s long-lost twin and wants revenge because our boy Sa-Eon got to move on and live a wonderful life, rather than be an orphan with no family or wealth. When the kidnapper is talking to Hee-Joo, he says something like, Nobody knows Sa-Eon better than me. Who knows a twin better than their twin, eh? The kidnapper is also specifically focused on Sa-Eon having the worst life, so this leads up to another theory for who he might really be. 

3. Is the kidnapper Sa-Eon? 

Okay, this might all sound a bit confusing, but in this theory, I’m referring to the psychopath kid as Sa-Eon. According to this school of thought, the kidnapper himself is the real Sa-Eon and is trying to take revenge. This theory also makes complete sense because we know that the guy had antisocial tendencies as a child, so of course he’d grow up to become a kidnapper, but how did he escape, and why aren’t his parents doing anything about it? We are most certain that Yoo Yeon-Seok’s Sa-Eon isn’t the real heir of the company because his “mother” spits on the chairperson’s picture in rage. This is because she had to make a difficult choice 20 years ago. This choice obviously had to do with the “killer” kid, which is why she essentially hates her own son. 

4. Is Do-Jae The Twin? 

Now we know the kidnapper has nothing against Hee-Joo, which is why he was happy to see her use his phone and go about her business, which would help him see Sa-Eon miserable. But, it seems the kidnapper has another accomplice, or rather a sort of boss, and a lot of people think it’s Do-Jae, his assistant, because he’s the only one wearing black at the office retreat, and the person who pushed Hee-Joo was also wearing black. If this is the case, then Do-Jae could be the twin and might think of Hee-Joo as a threat. I can’t really understand why else he would hurt her.

5. Is Do-Jae Sa-Eon? 

Now if Do-Jae is actually the bad guy and he’s not the twin, then could he be the psychopath himself? This theory also doesn’t make full sense because his parents would probably recognize him? Unless whatever happened 20 years ago stopped them from seeing the boy completely. I guess being a competent employee so close to Sa-Eon would make it so he doesn’t look suspicious at all. But, in all honesty, again, personally, I don’t think he’s the bad guy, but who knows? 

6. Is In-A The Bad Guy? 

Now here’s the deal. In-A forced Hee-Joo not to talk for years for her own benefit, but now she wants her to talk again. It looks like In-A might actually like Sa-Eon, but maybe she knows the truth about who he is, which is why she refused to marry him. Or she just wants to see her sister suffer, which I would absolutely hate. We don’t need that girl-on-girl hate! 

7. What If The Kidnapper Is The Dead Brother? 

Okay, this is the last theory I’ve heard, and it sounds bonkers, but what if the kidnapper is In-A and Hee-Joo’s dead brother? We don’t know much about this accident, and you know how rich people can hide evidence, etc. Maybe the accident left the kid “abnormal,” which is why the family chose to hide him. There are two ways this could go: one is that the person who pushed Hee-Joo is the dead brother, or the kidnapper who calls Hee-Joo “unnie,” which is what girls call their older sisters in South Korea, is the dead brother. I think the former makes a lot more sense, and the latter is just a way for Hee-Joo to feel close to the kidnapper before he ruins everything for her, eh? 

Which of these theories do you believe? What is your favorite theory about When The Phone Rings? Let us know in the comments down below. 

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