The Protectors-Narmoto, Izotor, Vizuna, Kivoda, Nilkuu, and Korgot-meet in the Jungle Region of Okoto near the City of the Mask Makers at Vizuna's urging. Having witnessed the Toa defeat the Lord of Skull Spiders, Vizuna fears that they may require the Protectors' assistance in the city, and leads his comrades to a bridge constructed by the long-missing archaeologist Harvali. They are forced to contend with a group of Skull Spiders, who upon being driven off recover their defeated leader and begin taking him back to his lair. Meanwhile, the Protectors stumble across ancient carvings depicting the Elemental Creatures, Okoto's history up to now, and even an image of themselves meeting with Ekimu the Mask Maker.
After falling down a pit trap, the Protectors encounter none other than Harvali, who has been trapped in the city for some time. The group are able to free a biomechanical snake from a Skull Spider, and it then befriends them-Nilkuu especially-and carries them to the lair of the Lord of the Skull Spiders. The Protectors are then forced to engage hordes of Skull Spiders, which had been massing for an invasion of Okoto, and manage to collapse the lair with the Lord of Skull Spiders and many of his minions before making their way to the city's surface with the snake's aid. They are then forced to deal with a group of Skull Warriors, but find traces of the presence of the Toa in the city.
The Protectors and Harvali arrive at the forge of the mask Makers shortly after the Toa and Ekimu have battled Skull Grinder, and soon meet with the Mask Maker. After briefly mistaking them for their long ago ancestors, he gets their help in tending to the injured Toa while he repairs their mask. Afterwards, they launch fireworks to celebrate their victories and to announce to all the Okotans that it is safe to come to the ancient city and make it their new home. However, Ekimu senses the evil of his brother, Makuta, and knows that they have not seen the last of him.