1. Find the security system, which is the password door.

2. Ask the suspect to follow the prompts first, get the willow tree and keep it perfectly confidential.

3. On-the-spot investigation Click on the wet footprint of the exhaust fan with a screw missing from the fuselage, and the big machine in the middle can get a hidden dialogue.

4. Analysis of access records

The conversation with the suspect man showed his visit record and asked why there was a late-night guest at PM 1 1: 30.

The dialogue with the female suspect also showed her own access records and asked for an alibi.

5. Suspicion statement combines intelligence with late-night guests and perfect confidentiality in order to obtain secret saboteurs.

6. Flash powder Combine the flash powder with the loose shell to obtain information.

7. The murderer is a female suspect.

The evidence presented is an alibi, shrapnel information of wet marks, and finally Xu Zhitai's access record.