They do it with mirrors
Agatha Christie
Miss Marple (6)
Silks
Dick Francis
Dirk Gently's Holistic Detective Agency
Douglas Adams
Dirk Gently (1)
The Blood Mirror
Brent Weeks
Lightbringer (4)
Power Lines
Anne McCaffrey & Elizabeth Ann Scarborough
Powers Trilogy (2)
Power Play
Powers Trilogy (3)
Powers That Be
Anne McCaffrey
Powers Trilogy (1)