The Secret Scientists have combined their brainpower to solve a developing global crisis: water supplies in the Middle East are inexplicably turning into salt.
As part of Zak's training in his cryptid-influencing power, the Saturdays travel to New Guinea with Ulraj (the young king of Kumari Kandam) to investigate a dinosaur/bat creature called the Duah.
When Doc receives a troubling "visit" from what appears to be the ghost of his old mentor, the Saturdays travel to Louisiana's Honey Island Swamp to let Doc finish the work he and his mentor started over 25 years ago.
The Saturdays stumble across a hidden city built in the middle of an African lake, but this paradise in being threatened by repeated attacks from the giant, catfish-like Lau.
The Saturdays, Doyle and the Bedouin girl Wadi (from "Eterno," currently being babysat by the Saturdays) come across a small Chinese mountain village that's been blighted since the theft of its protector, a Blue Tiger.
Zak and Doyle, the only Saturdays who know about Fisk's newfound heritage, try to help the big gorilla-cat uncover the secrets of his Lemurian ancestry.
When Fiskerton is framed for a series of nighttime attacks on fellow Secret Scientists, the Saturdays are placed under house arrest by Dr. Beeman, Dr. Grey, and Agent Epsilon's "people."
Fiskerton's inherited Lemurian instincts are supposed to lead the Saturdays to where Kur will be revealed, but all they seem to be doing is driving Fisk nuts.
Returning home to their demolished HQ to gather up some old Sumerian tomes from Drew's library, the Saturdays are ambushed by Tsul'Kalu, the great hunter and previous owner of the Hand of Tsul'Kalu on the end of Zak's Claw.