As a result of a mysterious experiment, the volunteers find themselves locked for several months in sealed rooms at different levels of an unknown structure. Every day, a platform is descended from the uppermost level, packed to overflowing with delicious food. Everyone strives to grab a better piece. And what will then be left to the very last levels? But once a month, tenants change floors. And before the experiment, each participant could take only one object with him, the main character had a book "Don Quixote", and his "cellmate" had a sharp self-sharpening knife.