Dead Air is a Nazi Zombies-related hidden achievement/trophy, available in Call of Duty: World at War. It requires the player to activate the easter egg song "The One" on Shi No Numa. It is done by holding the 'use' button on the disconnected telephone on the desk in the Comm Room four times.The player will first hear a sound of the phone being connected again, then the sound of numbers being pressed three times. The player knows the achievement/trophy is complete when a disembodied voice, similar to the radio in the Doctor's Quarters, announces "I know when you're sleeping" very slowly. A chime will then play and the song will then play.