Panic Room is a mini-game that can be unlocked by collecting a certain Gnome.
This mini-game, like most, is in the practice room. There are various items around it, and a cage in the middle. Nick is here.
The goal of the level is to break out of the cage and get the gnome. Only Remote View is allowed, and there is a Sniper Rifle with six bullets. The player must figure out how to break out. After all six shots are fired, a forty second timer will start, and Nick has to collect the gnome.