Absinthe.

Newly-engaged Conor and Roxy celebrated a small, impromptu engagement party with a close group of friends at a relative’s lake house. Thomas Mitch, a filmmaker, was in attendance. Conor, knowing that Mitch would attend, used the opportunity to work on his junior psychology dissertation project: a collection of video interviews. Mitch brought his Canon XH-A1 HD video camera with him and began recording. The camera was found, still recording, by the police. They refuse to release the tape. Was absinthe the cause of the murders? You decide.