The Decagon House Murders by Yukito Ayatsuji

Title: The Decagon House Murders

Author: Yukito Ayatsuji (Translated by Hong-Li Wong)

First published on 5th September 1987; republished by Pushkin Vertigo in 2020

Genre: Mystery and Thrillers

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Rating: 5 out of 5.

The members of a university mystery club decide to visit an island which was the site of a grisly murder-suicide a few months ago. The island housed a renowned architect named Nakamura Seiji. Blue Mansion, the house in which Nakamura Seiji lived along with his wife was burned down in the fire – their burnt corpses, along with those of the husband-wife house-helps were found a day after the incident.

The seven university students on the island are nicknamed Ellery, Van, Agatha, Orczy, Poe, Leroux and Carr. Agatha is confident of everything while Orczy has low self-esteem. Carr seems to be full of himself and the rest of the team do not like him much. Van’s uncle is a real estate agent and has purchased the ‘Decagon House’ on the island – the house which the students will occupy for a couple of days. Everything in the house is in the shape of a decagon – including the house itself, which is built in a decagon shape. There are ten rooms in total; the tea cups and tables are also in the shape of a decagon.


The next morning, Orczy wakes up to see a number of plates on the table – painted with threatening words. First Victim, Second Victim, Third Victim, Fourth Victim, Fifth Victim, Murderer and Detective. The students believe someone is trying to scare them – it might be a prank. But the next day, one of their friends is found dead and the victim’s left hand is chopped off; when Nakamura’s wife’s corpse was found, her left hand was missing.

Is someone playing a trick on them? A sinister trick that results in their deaths? Sounds like And Then There Were None all over again!

The first Japanese translated mystery I read was Murder in a Crooked House and I did not like it. Some stories are ‘lost in translation.’ It is not easy to get the same emotions and meaning in the right way (or in a way that makes sense) while translating a book. However, I am glad I gave The Decagon House Murders by Yukito Ayatsuji a try because I LOVED IT!

This can be a perfect Halloween read. The story has a dash of spooky – something to do with the sightings of a ‘ghost’ on the island. *plays eerie music in the background* I wouldn’t compare The Decagon House Murders to Christie’s And Then There Were None. Though the plot sounds similar, the former has two settings – 1) scene of the crime 2) not a scene of the crime 😀 (Cannot make this review a spoiler by giving away the details of the second setting.)

The first half of the story is all about character introductions and setting the scene of the crimes. The second half alternates between the island and solving the mystery. *no more spoilers*


I found the nicknames amusing. Agatha is angry that the men leave all the cooking and cleaning to women.

“When it comes down to something like this, we women are always the worst off, aren’t we? They think we’re their servants,” Agatha grumbled as she quickly took care of the dishes. Orczy stood beside her, staring at the white, supple fingers swiftly doing their work, until she realized she wasn’t doing any work of her own.

“Let’s have the boys do some work in the kitchen, too. They shouldn’t think they’re off the hook just because the two of us are here. Don’t you agree?”

Aggie is also annoyed that the coffee is of the instant kind.

Let me give you a juicy piece of gossip. A while ago, Carr made advances to Agatha and was rebuffed. Is LOL the right ‘sentiment’ here?

As the story ends, we get to know their real names – it was difficult for me to remember as I was used to calling them Ellery, Carr, Agatha, Orczy, Van, Poe and Leroux. If you are aware of the Original Mystery Club, you might find a name or two missing…

The setting was a little eerie and this might very well the reason for my nightmares – I have hardly had 6 hours of deep sleep since reading this book. (Maybe I shouldn’t keep grisly murder mysteries as a bed-time read!) I loved the setting(s) and the characters. The twist in the second half of the story kept me hooked until the end. Speaking of endings, gosh, I did not see the final twist coming. I was like, HUH? WHAT???

If you love locked room mysteries, you might want to give The Decagon House Murders by Yukito Ayatsuji a read.

Second Opinions:

Kate @crossexaminingcrime; Bev @myreadersblock; Anjana @superfluousreading; John @countdownjohn

I received an ARC from Pushkin Vertigo and Edelweiss+ in exchange for an honest and unbiased opinion.

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6 thoughts on “The Decagon House Murders by Yukito Ayatsuji

  1. This sounds creepy and so interesting.. I’ll have to read it when I get the chance.
    Great review, Rekha, thanks!

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