A wealthy businessman named Han Zhihao had been found dead inside his private study.
The evidence initially seemed overwhelming.
The security cameras showed that nobody had entered or left the study during the estimated time of death.
The murder weapon, a decorative crystal knife, was found inside the room.
More importantly, the victim's blood was found on the clothes of his son, Han Yu.
Han Yu was immediately arrested. The prosecution's case was almost airtight.
There was a motive as well.
Han Zhihao had recently discovered that Han Yu wasn't his biological son and had planned to remove him from the family inheritance.
Several witnesses had even heard the two arguing violently the night before the murder.
Yet there was one problem. Han Yu repeatedly insisted that he hadn't killed his father.
"I didn't do it. I swear I didn't!"
But nobody believed him.
The most troublesome part was Han Yu's mother.
