When their class was canceled due to the train that Ms. Swift and the passengers in the subway went missing, Zick and Elena along with Bombo investigate the subway find that a Megarock has eaten the train and they were able to save the passengers. They later learn that Hector Sinistro was using the worm monster to try to attack to Ancient Armory underneath by kidnapping and threatening its babies to do his bidding.
Un treno e i suoi passeggeri (tra cui l'insegnante di Zick ed Elena) scompaiono. Così i due ragazzi, insieme a Bombo, indagano sulla metropolitana, scoprendo che un Megarock ha mangiato il treno.
