Detective's Reasoning: Major Case Base, Issue 4

When the phone rang, TV actress Asai Miyoko was putting on makeup at her vanity. She reached out and picked up the receiver. "Do you have the money ready as I told you?" As soon as she heard the man's voice, Miyoko couldn't help shivering. "Um... ah... trying to..." "Then, let's make the delivery today." "Where?" "Near Hikarioka Station, there's a Hikarioka Apartment. Come to Room 508 in that apartment." "What time should I come?" "Whenever you're convenient." "Well, how about 1 p.m.?" "Okay, I'll wait for you." The other side let out a harsh laugh and hung up. Miyoko stayed still, forgetting even to put down the receiver. After thinking for a while, she made up her mind and took a capsule from the vanity drawer. "Give him the money in exchange for a copy of my medical record, but he has surely made many copies. I have to be ruthless and use this poison secretly... not sure if there will be an opportunity..." Miyoko stared at the powder in the capsule—it was potassium cyanate. A few days ago, when she stayed at her sister and brother-in-law's house, who ran a pharmacy, she had secretly stolen it from the shelf of highly toxic drugs. Two years ago, Miyoko had been seduced by a TV station director and, after becoming pregnant, had an abortion. She didn't know how the recent blackmailer had obtained her hospital medical card from when she was hospitalized and was now using a photocopy to extort her. When the phone rang, professional tennis player Tomoda Koichiro was in the bathroom. Hearing the ring, he hurriedly ran out of the bathroom and immediately picked up the receiver. "Do you have the money ready as I said?" Upon hearing the man's voice, Tomoda straightened up instantly. "Ah, trying to..." "Then, give me the money today." "Where?" "Near Hikarioka Station, there's a Hikarioka Apartment. Come to Room 508 in that apartment." "What time?" "How about 2 p.m.? Well, looking forward to your visit." The other side let out an unpleasant laugh and hung up. Tomoda Koichiro held the receiver tightly, thinking for a long time. Once he made up his mind, he took a small medicine bottle from the desk drawer. The bottle contained potassium cyanate, which Tomoda had secretly taken last night from the highly toxic cabinet in the electroplating factory at his wife's house. The bottle cap was sealed with glass paper. One morning, an accident occurred that made Tomoda anxious and fearful. He played mahjong all night and, on his way back, his car ran over a junior high school student delivering newspapers.In the early morning, just as the sky was turning light, fortunately no one saw, Tomoda abandoned the student he had hit and sped away. However, he did not know where the blackmailer had been watching and had taken photos of the scene to extort him.\ When the phone rang, the innocent-type singer Mayumi Kato was having breakfast alone in the kitchen, although it was already late. "Do you have the money ready that I told you about?" At the sound of the man's voice, Mayumi shivered all over. "Well... um..." "Hand the money over to me today." "Where?"\ "Near Hikarioka Station, there is a Hikarioka Apartment, come to Room 508 of that apartment." "Well... I promised to go out for a drive today, so..."\ "Hey, which do you think is more important, going for a drive or our deal? Anyway, come anytime between 1 PM and 3 PM, I'll be waiting." The other party threatened and hung up.\ Mayumi held the receiver, stared blankly for a while, then resolutely took from a drawer in the cabinet a paper package wrapped in a handkerchief, containing about half a spoon of potassium cyanide.\ It was the potassium cyanide left behind from when her cousin, who worked in literature, committed suicide two years ago. Mayumi had feelings of admiration for this cousin. She, full of sadness, had kept this potassium cyanide as a keepsake.\ "As long as I retrieve the copy, I'll use this medicine to settle the problem once and for all. It's too hard to deal with the blackmail again and again; I'm not sure if I have the courage..."\ A theft she committed in high school filled her with deep regret. During summer vacation, she went shopping at a department store, and suddenly, as if bewitched, stole perfumes and cosmetics. She was caught and received a severe reprimand. The blackmailer somehow got hold of those police records from that time and is using a copy to extort her.\ The next day's (August 5th) morning paper published a report: “Reporter Koichi Watanabe found dead in Room 508, Hikarioka Apartment, XX Street, XX Ward.”\ The deceased was discovered by the owner of the apartment, Mr. Masaharu Uesaka. Mr. Uesaka said he had gone on a trip three days ago, and during his absence, his friend—the victim—borrowed this room.\ The cause of death was potassium cyanide poisoning. The estimated time of death was between 1 PM and 3 PM yesterday. A glass of juice on the table had not been finished; the juice contained potassium cyanide.\ The room had air conditioning, which was on, but for some unknown reason, the window was also open. The interior had been rummaged through, so the police considered it a homicide and had already begun an investigation.That afternoon, from 1:30 to 2:30, the area around this apartment experienced a power outage for about an hour. A truck driver, due to fatigue driving, crashed into a utility pole and cut the power lines. After reading this news, Miyo Asai thought to herself: 'When I returned from the apartment, the elevator had just stopped on the first floor because of the power outage. Luckily, the timing was perfect; if I had been even slightly later, I would have been trapped in the elevator. My luck was good at a critical moment, I got things done smoothly. That man is dead, how delightful.' Koichiro Tomoda also read the news: 'Hmph, serves him right, now it's peaceful. However, I didn't notice the power outage at the time. I was afraid of encountering someone, so I didn't take the elevator and went up the stairs, but ended up meeting two housewives on the stairs, unlucky. But I was wearing sunglasses, so no need to worry. Room 508 isn't that guy's residence, quite unexpected.' Mayumi Kato also read that news several times. 'On the way, on the road near the apartment, there were two patrol cars parked. I thought something had happened and was a bit nervous. Turns out the outage was caused by a truck accident. Luckily it happened during the day; it would have been bad if it was at night. When entering the apartment, all the onlookers stared at me, but I was in disguise, wearing sunglasses and a wig, so no need to worry about being recognized. But what if Officer Xing comes snooping here? ... Ah, doesn't matter, there is no evidence showing I went to that room... Anyway, that man is dead, no one will tarnish the image of the innocent singer.' So, detectives, among the three, who is the criminal that killed the blackmailer with potassium cyanide? Why? Reward: 50 million membership coins plus 1,000 knowledge points.