“I couldn’t find the tank, so I steeled myself and came here to try my luck. The moment I opened the door, there it was — the fish tank sitting right in the middle of the classroom, with a dead person floating inside. I was so terrified I wet myself on the spot. Look, my trousers are still damp.”

The young officer caught a sharp odor from Jiuwan and immediately wrinkled his nose in disgust. “How many keys are there to room 104?”

“One. Just this one.” Jiuwan held up a round wooden panel hung with jangling keys. Small holes ran along the inner ring, each holding a key, with the corresponding room location written above each hole in black ink.

“Have you ever lent this key to anyone?”

“Never. Where I go, the key goes. It never leaves my person.”

Just then, a shriek erupted from outside the door.

Bai Jin called the screaming girl over. “You know the victim?”

“Of course I do — this is Leng Yu from third year. She sat diagonally across from me.”

“When did you last see her?”

The girl thought for a moment. “There were evening classes last night. We finished at eight. After class everyone went home. I was on duty that day — responsible for locking up — and Leng Yu was the last to leave. I asked when she was going, and she said she’d wait a little longer.”

“Did you see her leave with anyone?”

“On her own.” The girl pursed her lips. “Don’t let her looks fool you — she had a withdrawn personality. She never mingled with anyone. Always went her own way.”

“Did she have any enemies?”

“Not that I’ve heard.” The girl shook her head. “What enemies could a student possibly have? Oh, by the way — handsome — was she killed by a person or by a ghost?”

Bai Jin raised an eyebrow. “Who told you ghosts can kill people?”

“Room 104 is haunted — everyone knows it’s the ghost of a girl in red who died a wrongful death. Yesterday was the fifteenth, and those kinds of ghosts love to pick days like that to come after people.”

“Alright, alright.” Bai Jin cut her off. “Sign here, please.”

Bai Jin turned to report his findings to Shi Ting. “Seventh Brother, what do we do now?”

“Let’s go take a look at the principal’s office.”

When the principal learned that visitors from the Military Police Bureau had arrived, he paid little mind — until he saw Shi Ting. His expression instantly shifted to one of warm deference. “Why, it’s Director Shi himself — what an honor. Please forgive me for not coming out to meet you.”

The Military Police Bureau might not wield the same power as the army, but Shi Ting was the Marshal’s own son — flattery was absolutely in order.

Shi Ting had no patience for pleasantries. He came straight to the point. “Where was the missing fish tank originally kept?”

“Right here.” The principal pointed to a bare corner of the room. In the absence of the tank, a rectangular mark was clearly visible on the floor, noticeably different in color from the surrounding area.

“This is strange.” Bai Jin crouched down to examine it carefully. “This spot is over fifty meters from room 104. A tank that size — how on earth did it get all the way over there?”

“What happened to the fish?” Shi Ting asked.

“I assumed the fish and the tank had disappeared together, but when the gatekeeper Jiuwan was searching for it, he found one dead fish in a rubbish bin. The rest were probably eaten by stray cats.”

The principal produced a paper bag and held up a shriveled dead fish, looking genuinely pained. “Look at this — fish I’d kept for three years. All dead. What a terrible waste.”

“How did you normally change the water in the tank?”

“I’d insert a siphon tube to drain the water, then replace it with water that had been left to sit. I kept the stored water beneath this cabinet.” The principal opened the cabinet door to reveal several iron cylinders, each filled to the brim with clear water.

After answering Shi Ting’s questions, the principal looked baffled. “Director Shi — surely this wasn’t actually the work of a ghost?”

—