Burn Notice2007

Michael Westen:
[narrative] Most commercial security systems use magnetic sensors. When a door opens, it breaks an electrical circuit and triggers the alarm. Which means defeating the system is just a matter of keeping a magnet in contact with the sensor. Unfortunately, very security-conscious people often customize systems with less-visible sensors... like a pressure plate in the floor that silently announces your presence and gives whoever's inside a chance to do something about it.