Placing this brass doorknob against a flat surface will allow a door to magically manifest that leads into a pocket dimension comprising if a small detectives office. There is a desk and a few chairs, a cork board, a slightly broken ceiling fan and a rusty filing cabinet.

The room provides advantage to investigation checks when used to ponder a mystery. 

The filing cabinet when told a name will produce a dossier of an individual's known public information 3x every 24 hours.

The desk can provide investigative tools as needed, and seems to manifest a bottle of scotch with a clean glass whenever it's needed.

While the door is in place and active anyone can enter.