Footage Erased: Anne the Suspect?

When David started the software to view the footage, he was shocked to see that the footage from that night was completely erased. Even all the footage from the other nights was gone. He couldn’t understand what could have happened. But he knew that someone had deliberately erased it. He wondered if Anne had something to do with it.

Anne was noticeably nervous and jumpy last night. Could she be the one who was coming in and erasing the footage? But why would she do that? David couldn’t think of a single reason why Anne would want to erase the footage.