Volume 10

Reika Yotsui
	Victim (drowned); 24 years old; Yotsui Group heiress;

Takuya Mifune
100px	26 years old; Mifune Electronics president;

	Volume 10
	Information
Release date:	April 18, 1996
Chapters:
ISBN:	ISBN 4-09-123380-5
Publisher:	Shogakukan
English release date:	March 21, 2006
English ISBN:	ISBN 1-4215-0316-6
English Publisher:	Viz Media
	Featured Detective & Keyhole
; Auguste Dupin	; Heiji Hattori
	Aoyama's death & Conan side images
	Chronology
Prev volume:	« Volume 9
Next volume:	Volume 11 »
	List of chapters • List of cases

Volume 10 was released on April 18, 1996 in Japan.

Cast

Characters

Gadgets

Voice-Changing Bowtie

Stun-Gun Wristwatch

Heiress Murder Case

Anime Episode 39-40: Wealthy Daughter Murder Case

Characters introduced

File 091 - The Water Time-Difference Trick

Conan pretending to be Kogoro is now presenting his deductions.

Show spoilers »

People

Mr. Yotsui
	Reiko's father Yotsui Group chairman

Takashi Ichieda
	26 years old City Bank main branch fund procurement division

Yuji Nikaido
	Victim (drowned) 27 years old AD agency sales department

Osamu Gojo
	24 years old Gojo Trading adjutant general

Masashi Rokuda
	40 years old Yotsui & co. LTD director

Yone Nanao
	64 years old Yotsui family housekeeper

Yakeo Nanao
	Deceased Yone's granddaughter

Great Detective of the West

Anime Episode 48-49: Diplomat Murder Case

Characters introduced

Heiji Hattori
	17 years old High school student Detective

Heizo Hattori
	Heiji's father Chief of Osaka Police District

Yukiko Katsuragi
	24 years old Takayoshi Tsujimura's girlfriend Student at Touto Medical School

Takayoshi Tsujimura
	27 years old Isao Tsujimura's only son Legal apprentice

File 092 - The Great Detective Of The West

During a phone call with Ran, Conan pretends to be Shinichi, but his sneezes interrupt the conversation. When Ran asks him to come home, he excuses his absence with being on a tough case. Before he can say any more, Ran hangs up to answer the front door. Conan mentally grumbles about Ran's worried behavior as he walks home. He arrives to find a teenager in a baseball cap demanding that Ran stop hiding Shinichi. Conan sneezes, attracting Ran's attention, and she comments that Shinichi is also sick. The teenager asks how she knows, and Ran explains Shinichi's phone calls. The teen concludes that Sonoko's was right about them being together, to Ran and Conan's embarrassment, and asks if Shinichi ever asks how Ran is doing rather than talking solely about himself—to care enough to call but not ask after her, Shinichi is probably watching Ran from close by. As Conan wonders in shock who the teenager is, the teen takes off his cap and introduces himself as Heiji Hattori, another high school detective.

Conan sneezes again, unimpressed. Heiji explains that although Shinichi stopped appearing in the papers, people still compare Heiji to Shinichi, and Heiji wants to know if Shinichi is really a comparable detective. He also gives Conan a "cold cure", which turns out to be alcohol that he presents to Kogoro as a visiting gift. Another knock interrupts them, as a client, Kimie arrives with a request that Kogoro investigate her step-son's girlfriend, Yukiko. Kogoro comments that Yukiko appears perfect, and Heiji concludes that Kimie is suspicious about the perfection. Kimie wishes to have Kogoro also consult with her husband, Isao, in a low profile meeting at their home because Isao is a diplomat; Heiji convinces them to bring him, Ran and Conan along. Conan agrees in order to keep an eye on Heiji and what he might say, despite the alcohol having worsened his symptoms, while Heiji hopes that Shinichi might show up if Ran is along on the case.

At the house, Kimie introduces Kogoro as an old friend to the butler, Fumio. Before they get further, Yukiko arrives at the house and greets Kimie as "mother". Her presence shocks Kimie, and she angrily forbids Yukiko from calling her mother even though her step-son, Takayoshi, invited Yukiko over in order to meet Isao. The group also meets Isao's father, Toshimitsu, on the way to Isao's study. Toshimitsu, Takayoshi, Yukiko, and Fumio realize that Kogoro is actually a detective, and wonder why he would be there. At the study, Isao doesn't answer Kimie's knock, and she unlocks the door to reveal him sleeping sitting up at his desk, head propped on his arm. Heiji notes the opera playing while Kimie shakes Isao and tells him to wake up, only for Isao to fall to the floor, dead.

File 093 - Double Reasoning

Heiji pronounces Isao dead, to Kimie's horror, just before the rest of the household arrive and learn what occurred. Kogoro calls the police while Conan examines the body, noting purple lips and a red dot near the base of the hairline; just as he spots what looks like a needle, Conan knocks heads with Heiji, who was similarly investigating. To Conan's annoyance, Heiji drops Conan back with Ran, saying that kids shouldn't be seeing dead bodies.

Heiji reminds Ran of Shinichi.

When the police arrive, Kogoro starts to tell Megore that Isao's death was an accident, but before Conan can say otherwise, Heiji interjects that Isao was poisoned. Heiji explains the evidence that Isao was poisoned using a needle by someone with access to the house within 30 minutes of the group's arrival. Megure recognizes Heiji as the son of Heizo Hattori, Osaka prefecture's chief of police, though Heiji doesn't seem to appreciate the reminder. As Heiji talks with Megure, Ran is reminded strongly of Shinichi. Megure notes that the only entrance to the room is the locked door, which requires a key. Kimie reports there being two keys: hers, which she used to unlock the study, and Isao's, which they find still tucked into his pocket. The case is suddenly a "locked room murder".

Heiji notes Kogoro's surprise at the revelation, and privately takes it as confirmation that Shinichi is telling Kogoro over the phone how to solve the cases. Heiji is determined to solve the crime first, and prompts Megure to check the alibis for the time window of the murder. The suspects give their alibis, and the suspicious alibis are Toshimitsu, Takayoshi, and Yukiko. Megure investigates the room and finds Isao's classical music collection (though opera was playing when they arrived) and a photo from 20 years ago that Conan can see well because the alcohol has made his symptoms steadily worse and now his vision is blurring. An officer also redraws attention to the random books stacked in front of Isao as if grabbed off the shelf haphazardly, before two other CSI officers discover that Isao's keychain slides into two halves and scotch tape with a bump is inside. Conan tries to see, but Ran picks him up and admonishes him to stay out of Heiji's way, before she returns to watching Heiji with a smile on her face, to Conan's confusion. Before Conan can say anything, his chest spasms, while Heiji has a thought and dashes to a different room in the house. Both detectives mentally declare they've discovered the trick, just before Conan collapses in the study.