Eden, Eli, Marwan, and Ilanka barely know each other beyond having a class or two together. But when they are all summoned via messaging app to an empty classroom after school, they find a small cube sitting on a desk. Its sides light up with rules for them:

'Do not tell anyone about the device. Never leave the device unattended.'

And then, 'Take me with you... or else.'

At first they think it's some kind of prank or a social experiment orchestrated by the school administration. Still, they follow its instructions until the newly-formed group starts to splinter. Nobody has time for these games - their lives are complicated enough. But the device seems increasingly invested in the private details of their lives. And disobeying its rules has scary - even life-threatening--consequences...