A cryptic letter leads the player to the attic of an abandoned house, where an elaborate cast-iron safe conceals a succession of increasingly intricate mechanisms. By examining every surface, collecting objects and manipulating locks, dials and hidden compartments, the player must uncover the secrets contained within.

A mysterious eyepiece reveals markings and mechanisms invisible to the naked eye, while scattered notes gradually expose the previous owner’s research into an enigmatic substance known as the Null. Progress depends on careful observation, spatial reasoning and the tactile manipulation of three-dimensional puzzle boxes.