The Quiet Box: Simple and elegant, this strange, glossy black cabinet with gold trim is a miniature prison for one. The only way to release a captive from its velvety purple interior is to put another prisoner inside. It is said that the quiet box causes its prisoners to lose their grip on reality. Those placed inside can neither see, hear, nor smell anything. after a prolonged imprisonment, a captive feels unnaturally relaxed, eventually loses all sensation, and is left unable to think clearly when released.
The quiet box was a specialized prison cell usually reserved for extremely dangerous, and powerful beings. There are two mentioned in the series: The one at Fablehaven, and another at Living Mirage. Both of them contained, for a long time, Navarog, the Black Dragon, and Nagi Luna, an extremely powerful and evil Demon respectively. Eventually, however, each of them was emptied of their prisoners, and were then inhabited by a Narcoblix, and a Human, respectively.