In the metro, underground, active and curious creatures — metronomes — have been living for many centuries. They keep the underground order and protect the earth’s crystalline network. Each city where the metro runs has its own crystalline network and its own metronomes, which guard it from metroloms — dark underground creatures that feed on mold and dream of filling the entire underground world with dark energy. Every day, metronomes fight metroloms, preventing darkness from defeating light. One group of metronomes lives in the Moscow metro and quietly helps people every day.
