Episode Summary
Qi Sizhe proves his innocence in the poisoning case by revealing the cyanide was in the victim's medication. He forces his way into the investigation of a frozen body found in a bathtub. The police track down a suspect named Zhang Lu who links the two victims. Han Feng moves to arrest her, but Qi Sizhe insists she is innocent.
Spoiler Alert
The Soda Water Mix-Up
We pick up right where we left off with the poisoning mystery. Qi Sizhe is already steps ahead of the police. He figures out the cyanide was sitting in Qiu Lanzi's system before she even took a sip of water. The autopsy backs him up.
Han Feng grills Qi about why he transferred to this unit. He suspects it connects to past events. Qi keeps his mouth shut. Han Feng admits he doesn't think Qi is a killer. But he doesn't care about gut feelings. He only cares about the evidence.
The lab results come back on the water bottles. They were clean. Qi Sizhe pieces the puzzle together with some leaked info from Zhu Qingyue. The killer spiked Qiu Lanzi's stomach medicine. Usually, the capsule takes time to dissolve. Qiu Lanzi had terrible luck. She grabbed Qi's soda water by mistake. The carbonation sped up the reaction. Dr. Zhao tests the last pill in the bottle and confirms it. It was cyanide.
This clears Qi Sizhe of murder. He immediately tries to join the investigation. Han Feng shuts him down. He tells him to stay away.
The Frozen Corpse
Zhu Qingyue does some digging on our mysterious medical examiner. Chief Bai spills the tea. Qi Sizhe survived a horrific car crash two years ago. A female passenger died. Qi rehabbed in one year when it should have taken three. He is brilliant but incredibly stubborn. Chief Bai actually wants Qi and Han Feng to work together.
Qi Sizhe doesn't listen to orders. He heads to Jiang Fei's house that night. Han Feng tails him. The police know Qi shows up wherever Jiang Fei appears. Han Feng demands answers. Qi finally gives a little ground. He admits he is tracking people connected to a woman named Yu Fei's death. He is also looking into a "Raw Diamond" case.
Qi enters the crime scene. He states that Jiang Fei didn't die of natural causes. Someone froze him to death in his own bathtub. Zhu Qingyue brings a team to re-examine the house. She agrees with Qi's theory.
A Bloody Clue
Qi Sizhe pushes to join the team again. Zhu Qingyue makes a deal. She brings him into the discussion but demands honesty later. They analyze the scene. There is sliced sausage on the table but no knife. Jiang Fei has no external wounds.
They spray Luminol. It reveals blood traces. The theory is simple. The killer cut themselves while slicing the sausage. They took the knife with them to hide the evidence. They find a single drop of blood left behind. It doesn't match anyone in the system.
The Girl in the Lolita Dress
Han Feng splits the team. He takes Wan Guoxin to a nightclub Jiang Fei visited. The owner shows them surveillance footage. Jiang Fei met with a girl wearing a distinct Lolita dress. Her name is Zhang Lu.
Zhu Qingyue finds a connection on the other side. The first victim, Qiu Lanzi, made frequent calls to a chemical factory. Her phone also held photos of Jiang Fei's arm. Gao Yuan remembers something crucial. Qiu Lanzi noticed a fluorescent tattoo on that arm.
It turns out Zhang Lu works at that chemical lab. She was also high school classmates with Qiu Lanzi. The pieces start falling into place. Han Feng learns the two women argued recently.
The Wrong Suspect
Police bring Zhang Lu in for questioning. She seems genuinely shocked that Qiu Lanzi is dead. She offers a weird detail. She claims Qiu Lanzi called her to say Jiang Fei was dead. Qiu Lanzi also claimed she saw Zhang Lu's name on the corpse.
Dr. Zhao finishes his comparison tests. The evidence points to Zhang Lu. Han Feng orders her arrest. He thinks case closed. Qi Sizhe watches from the sidelines. He speaks up. He says Zhang Lu is not the killer. They caught the wrong person.
