Either Director Ba and the others deliberately avoided getting involved in their fight, or Zhang Jingfeng was daft! He actually grabbed a handful of hair from Han Kuan's head, causing Han Kuan to scream in pain!
After the police finally separated them, Han Kuan's nearly bald head had lost a few precious handfuls of hair! Seeing that neither of them could provide any important information, Zhao Yu asked the police to take Huan Kuan back to the police station, while he decided that he would Zhang Jingfeng away himself later.
Zhang Jingfeng was an unemployed gambler. As he was one of the important people in Han Kuan's case, the police had already checked out what he was doing on the night of the murder. That evening, it turned out that he had really been playing cards with his friends. So, he had a solid alibi.