[Since this post is about the ending of Persona 4, it obviously contains spoilers. You have been warned and I would not recommend reading ahead if you plan on playing the game at any point (which I highly recommend!)]
In Persona 4, the story took me through twists and turns in my 101 hours of gameplay as I tried to identify the real villain behind the Inaba serial murders. Unfortunately for me, I had this final deduction spoilered as I was reading about the game throughout my playthrough. Even so, when ****** was confirmed to be the killer, I was a little surprised since I hadn’t really paid attention to him throughout the game.
So I asked myself the question: Was it really possible to deduce who the killer was based on the information the game had given me? Through the exercise below, you’ll find that the answer is a definite yes.
After you and your friends decide not to throw (literally) Taro Namatame into blame as the culprit behind the murders, the game presents you a decision to identify the true culprit among pretty much all of the characters you’ve met in the entire game. For reference, I’ve put all the names in a table we’ll be working with throughout the deduction process:
First, I will list out the facts that we will use for the the deduction (in order). Some of these facts/assumptions are flimsier than others, so we’ll save them for last:
- People who do not yet have access to their Personas cannot enter or leave the TV world and also cannot throw someone into the TV world.
- Taro Namatame and Mitsuo Kubo are confirmed not to be the culprit due to your investigation up to this point.
- The culprit must have a relatively large stature in order to throw people (efficiently and quickly) into the TV world (Kanji is the heaviest victim at 143 pounds).
- The culprit has been able to monitor what you, the protagonist, have been doing and also knows where you live in order to deliver the warning letters (in October).
- No one was found to be suspicious in Inaba during the first two incidents, so the culprit must be able to blend in while living in the town.
- Yasogami High is known to be a school where gossip spreads like wildfire. However, after the protagonist receives the first warning letter, the following conversation happens, indicating that no one at school knows about the group’s abilities and adventures:
- Yosuke: Teddie’s been saying for a while that when we’re over there, he senses someone watching us… Wait… Every time we went to the other side to rescue someone, did we end up on the Midnight Channel ourselves…?
- Chie: I-I dunno… It seems like no one else knows what we’re doing. I haven’t heard any rumors about us at school. Even the people who I know check that channel haven’t said anything… The only gossip I heard was about the people who disappeared.
- The culprit has associations or at least has interacted with the announcer, Mayumi Namano, and the high school student, Saki Konishi, since he/she killed them by throwing them into the TV.
Deduction (cue music)
From here, we can start narrowing people down. From the fact #1, we can eliminate our teammates (Yosuke, Chie, Yukiko, Kanji, Rise, and Naoto), since we know that none of them had their Personas before the first two murders. We’ll make an exception for Teddie since he’s a shadow but we’ll get back to him later. Our table now looks like this:
Fact #2 is straightforward and allows us to eliminate Mitsuo and Namatame:
From fact #3, we can eliminate all of the shorter people/children, since they wouldn’t be able to efficiently and quickly throw people into the TV world. This eliminates Hisano, Shu, Ayane, and Nanako, leaving our suspect list at:
Fact #4 eliminates a few people for two different reasons. Mayumi, Saki, and Morooka were not alive in October to deliver you the warning letters. Misuzu Hiiragi (Namatame’s wife whom he cheated on) could not have known your address or be able to monitor you, so she is out as well. This updates our suspect list to:
We know from fact #5 that when Mayumi Namano and Saki were murdered, no one was suspicious in Inaba, so this eliminates Teddie. We know that he didn’t have a body at this time so even if he could come in and out of the TV, his costume would be beary suspicious to everyone in the town. Only 10 suspects remain:
Fact #6 tells us that no one from Yasogami High could be the culprit. This eliminates Kashiwagi, Hanako, Ai, Kou, Daisuke, and Naoki (and Yumi if you picked theater instead of band). Note that it is technically possible that one of these people just did a really good job hiding their knowledge of the group’s activities, but fact #7 (see below) also supports their elimination from our suspect list due to the fact that none of these people have known relations or interactions with Mayumi Yamano before she died. This is our table now:
Lastly, fact #7 from above tells us that our culprit must have interacted with Mayumi Yamano and Saki at some point to murder them. This is the flimsiest argument as we have no way to prove this, and it eliminates Sayoko and Eri (but not Dojima and Adachi since they are detectives and have interacted with the two). Finally, our table looks like this:
At this point, we are out of facts, but the game gives you three chances so you should be all set to guess between Dojima and Adachi. However, we can actually eliminate Dojima with a relatively solid assumption: Dojima has been more or less leading the investigation on the serial murders (whereas Adachi has only been assisting him), so there’s no good reason for him to leave behind a trail that could possibly point back to him as the murderer. In the end, Adachi is our culprit and the game confirms this in the story.
I’ve read thoughts from people saying that it was obvious that Adachi was suspicious from the start, but I did not get that vibe from him. Instead, I enjoyed the way that Persona 4 led us (sometimes in circles) to get to identifying him as the killer in the good/true ending. To me, a good murder mystery often means that the conclusion is not obvious, and this deduction exercise proved that it really took some work to catch the murderer in Inaba.