Trains bound for other worlds constantly capture innocent humans as waiters, and Lu Yang unfortunately falls into the trap.
In the infinitely long train, each carriage is inhabited by many strange passengers, including man-eating werewolves, evil spirits who like to kill people, and void monsters that create nightmares and other existences that are malicious to humans.
There are also cold elves, indifferent trees, and other existences that are neither good nor bad to humans.
There are even Bodhisattvas and angels who love human beings so deeply and are willing to protect human existence.
However, the advent of a key that can control trains changes everything.