The initial investigation into Wang Feng's call records from that night had already identified the delivery person who had brought him takeout.
Zhang Hui discovered the surveillance footage showing the delivery guy entering the neighborhood through the front gate.
The time was eleven twenty-eight, and the delivery guy left through the front gate at eleven thirty-two.
The information from the surveillance video matched the information provided by the delivery guy.
After 11 p.m., not many people were coming in and out of the neighborhood, which made Zhang Hui's investigation much easier.
"Check the back gate surveillance."
After the delivery guy left, Zhang Hui continued to review about an hour of footage from the front gate but did not spot Wang Feng.
He asked security to open the back gate footage: "Start playing from eleven thirty-two onward."
"Okay, hold on a moment. Our equipment here is over a decade old, so it takes a bit of time to access."
