Unusual Call Box

Unusual Call Box is a special encounter in Fallout.

Overview
When the Vault Dweller enters the map, all that can be seen (beyond the usual desert dust) is a large blue police call box. When the Vault Dweller approaches this unusually-located object, the light on top starts spinning, and the box slowly vanishes into thin air with a whooshing sound, leaving behind only a motion sensor.

Behind the scenes
The Unusual Call Box is a cultural reference to the TARDIS from the British sci-fi television series Doctor Who, as evidenced by the encounter's map and script names both being 'TARDIS'.