The show centers around the Saturdays, a family of cryptozoologists and part of an organization called the Secret Scientists who study the unexplained mysteries of the world in secrecy. The family is made of the 11-year-old Zak who has the power to control cryptids, his Genius Bruiser father Doc, his Action Mom Drew and his adopted cryptid siblings: a bipedal gorilla-cat known as Fiskerton (Fisk for short), a genetically modified Komodo dragon named Komodo, and a female Tropeognathus pterosaur called Zon. They travel across the globe dealing with cryptids while also having to foil the machinations of V.V. Argost, the enigmatic host of the hit paranormal show Weird World who uses his program as a front for his scheme to gain power over Kur, the God of Cryptids, and take over the world.
1: The Kur Stone Pt. 1
Reappearing after an 11-year absence, Argost searches for the Kur Stone, a relic that details the clues to unlocking Kur's tomb and power. The Secret Scientists had stolen the stone from him and split it into three pieces 11 years ago, but now Argost has managed to find two of the pieces. For the Saturdays, Argost sends two mercenaries named Van Rook and Doyle to retrieve information from them.
2: The Kur Stone Pt. 2
Having gotten the information he needed from interrogating a friend of the Saturdays, Argost heads to Brazil in search of the final piece with the Saturdays are in hot pursuit of him. In the Amazon Jungle though, Argost is the least of the family's worries as the stone is protected by a Tapire-Iauara
, meaning Zak will have to use his still-nascent cryptid-controlling powers.
3: The Vengeance of Hibagon
The Saturdays receive word of a rampaging Hibagon
in Tokyo, which to their surprise is actually Secret Scientist Talu Mizuki trapped in the body of one due to a body-swapping disaster at the hands of crime lord Shoji Fuzen. Now Dr. Mizuki wants vengeance against the crime lord, and the Saturdays will have to convince him to see the errors of his bloodthirst.
4: The Ice Caverns of Ellef Ringnes
A fellow Secret Scientist exploring the Inuit tombs of Ellef Rignes finds the wolf-like guardians known as Amarok
have been awoken. Calling in the Saturdays, it turns out that Van Rook and Doyle are stealing artifacts from the tombs. The thing is that Zak has also lost his power-amplifying weapon and grappling hook known as the Claw in the snow.
5: Guess Who's Going to Be Dinner?
Doyle and Drew go out for their anniversary night, leaving Zak and his cryptid siblings under the care of alien-studying Secret Scientist Dr. Beeman. They trick him into going out to find a spaceship, leaving the whole house to themselves, but the criminal Piecemeal, a gourmand with a steel jaw and a taste for the flesh of rare animals, sneaks into the house to check Fisk's name off his menu.
6: The King of Kumari Kandam
The Saturdays receive a report from a Secret Scientist that the lost city of Kumari Kandam
has surfaced. When the Saturdays arrive, Argost has made himself the king of its fish-like denizens and he orders the capture of the Saturdays. The family finds Prince Ulraj, the true heir to the late king, while Argost is steering the gigantic sea serpent Kumari Kandam rests on to destroy cities.
7: Van Rook's Apprentice
The Saturdays tangle with Van Rook and Doyle again when the mercenaries are sent by Argost to steal the horn of the Alkali Lake Monster
- a necessary component in finding Kur's tomb. During the battle, Doyle loses his mask, leading Drew to believe the face she saw was her younger brother long lost in the Himalayas when she was orphaned by mysterious attackers. Now, she sets out to prove it.
8: Twelve Hundred Degrees Fahrenheit
The Saturdays go to Chile when the erupting Orsono Volcano unleashes lizard-like monsters called Cherufe
upon the world. This time, Doyle is staying with them (to Doc's dismay), and they also find Argost and his half-spider lackey Munya searching for the crystals on a Cherufe egg - the next clue to Kur's tomb.
9: The Owlman Feeds at Midnight
The Saturdays and Doyle go to Cornwall in search of another clue to Kur's tomb. There, they find a quaint little town that fears a creature known as the Owlman
. At night, the dark secret is revealed - the townspeople are a bizarre cult hypnotized by the Owlman to give it human sacrifices. The cultists capture Zak as the offering while Doyle's tensions with Doc reach a breaking point.
10: The Swarm at the Edge of Space
With Doyle gone, the Saturdays rescue an aircraft under attack by a swarm of atmospheric jellyfish
. The passengers are Secret Scientist Agent Epsilon and his son Francis, who appears to do nothing but play a video game. However, the jellyfish turn to the Saturdays' airship instead, making their way into the interior and attacking its occupants. Now, Zak needs to figure out what's driving them crazy.
Water supplies in the Middle East are inexplicably transforming into salt, so the Saturdays are sent by the Secret Scientists to investigate. They discover the cause is the accidental reawakening of Eterno, a man made of salt cursed millennia ago to be eternally thirsty, by a young pickpocket named Wadi. Now Eterno is after the Methuselah Tree, the source of all water in the world!
12: Black Monday
In an Aztec temple, Zak makes the mistake of touching the Smoking Mirror of Tezcatlipoca
, knocking him out with a powerful blast. When he wakes up, he's finds out that he is in a bizarro antimatter universe home of the Mondays, evil opposites of the Saturdays that want to switch places with the real family.
13: Cryptid vs. Cryptid
The Saturdays find an underworld cryptid fighting ring run by Van Rook. Believing he is conspiring something with Argost, they re-hire Doyle to enter Fisk undercover as manager and monster respectively. While Doc and Drew try to figure out what Argost is up to, Zak, Fisk, and Doyle plan to bust out the encaged cryptids and put and end the bloodsport.
14: The Underworld Bride
The Saturdays and Ulraj travel to an island off New Guinea to investigate into the appearance of the pterosaur-like Duwa (aka Ropen)
. Zon falls in love with the creature, but Zak becomes afraid that he will never get to see her again if they become mates. His fears become justified when he learns of the terrible ritual the Duwa will perform on its lover.
15: Ghost in the Machine
Doc is visited by the ghost of his mentor Dr. Lancaster in the form of an EVP
, so the family go to Honey Island Swamp to complete his work of cataloguing the DNA of all cryptids. However, Zak, Fisk, and Komodo encounter the Honey Island Swamp Monster
and a team of Lancaster's former colleagues, who are using the database to create hybrid supercryptids.
16: Something in the Water
While relocating a Grootslang
, the Saturdays find a hidden environmentally-friendly utopia called Sanctuary II. However, the town is being terrorized by giant electric catfish called Lau
. The locals have hired Doyle to hunt the fish, but Doc and Drew soon find that Sanctuary II is not as idyllic as it seems.
17: Target: Fiskerton
Argost hires Van Rook and Piecemeal to capture Fiskerton when he believes that Fisk is Kur based on carvings he found in "Cryptid vs. Cryptid". The villains set the trap by luring the Saturdays and Doyle to Switzerland with fake cryptid reports. When the trap is sprung, Fiskerton is put in charge of protecting Zak, as Doc believes his son is the target.
18: Once More the Nightmare Factory
The Saturdays and Doyle head to Argost's deadly mansion where he hosts Weird World
(and where the Secret Scientists stole the Kur Stone years ago) to rescue Fiskerton from Argost's clutches. Meanwhile, Argost tries to gain Kur's powers from Fisk with little success until the Naga Queen, Rani Nagi, appears and reveals Fisk's true nature.
19: Curse of the Stolen Tiger
The Saturdays, Doyle, and Wadi are in China on the trail of a Maltese Tiger
stolen by Shoji from a Chinese village. The tiger supposedly grants good luck to those around it, but Zak is having anything but that, which everyone else attributes to the awkwardness of being around his crush, Wadi.
20: The Kur Guardian
The Saturdays call in Secret Scientist of ancient civilizations and Zak's former babysitter, Abby Grey to uncover information on Fiskerton's Lemurian origins (revealed when Argost captured Fisk). Their search brings them to Shangri-La, where they learn the history of Fisk's people, but Rani Nagi is on their trail in an effort to destroy Fisk.
21: Food of the Giants
The Saturdays, Doyle, and Abby go the Appalachians to subdue an Allegewi
terrorizing loggers. However, Van Rook is also in the area during the operation and he is obviously up to something. What the Saturdays will soon learn is that Van Rook has a new sidekick and there is a traitor is their midst.
22: The Atlas Pin
Argost steals Rani Nagi's Kur-finding relic, so the enraged Queen of Nagas threatens to pull out the Atlas Pin - an enormous undersea relic that ensures the world's tectonic stability. So, the heroes split up to save the world. Doc, Doyle, Fisk, and Zon go after Argost to take the relic from him while Zak, Drew, Komodo, and Ulraj have to stop the Nagas from pulling out the pin.
23: Paris is Melting
The Saturdays go to the Louvre, where the Smoking Mirror of Tezcatlipoca has been reconstructed and put on display. That's where they meet Zak and Komodo Monday again who want to use the mirror to draw out the family airship and cause chaos through the contact between matter and antimatter.
24: Where Lies the Engulfer
Doyle drops Zak off at an abandoned tourist resort in Canada to train him. The training session begins to go awry when they begin to notice something is not quite right with the water supplies in the area. It soon turns out the oddity of the water is caused by the nearby lake, which is in fact the living lake Hinqumemen
25: Shadows of Lemuria
Paraneurologist David Bara is called in by the Saturdays when Fisk begins to make strange signs subconsciously, wondering if Fisk's behavior is a clue to Kur. However, Argost is determined to retrieve information from Fisk's brain, so he sends a neuro-parasite to get the information, which starts to drive Fisk crazy. Meanwhile, Doyle repairs the Kur Detector he took from Argost.
26: Kur Rising
The Saturdays and Argost go to Antarctica, the location of Kur's tomb based on everything they've found. There, Argost awakens a massive monster believed to be Kur. The Saturdays fight back against the goliath while Argost manages to gain control of it from the inside. Now, Zak and Fisk enter the giant cryptid's body to stop Argost. But the most shocking reveal will come after the battle.
27: Kur Pt. 1
It has been six months after the revelation in Antarctica that Zak is Kur in human form due to the excavation of the Kur Stone causing Kur's power to enter the pregnant Drew's body 11 years ago. Now the family is on the run from the rest of the Secret Scientists (who want the Kur problem eliminated) with no home but their airship. Meanwhile, Doyle and Zon are teaming up with Van Rook to learn more about Argost.
28: Kur Pt. 2
As if the Saturdays didn't have enough problems already, the Nagas have declared war against the human race by sending an army of cryptids to terrorize the world. They send their monsters to New York City while deceiving the Saturdays into believing Hong Kong was the target. Meanwhile, Zak meets Argost and forms a secret deal to let the villain teach him to master his powers.
29: The Thousand Eyes of Ahuizotl
After getting the first of Argost's advice, Zak convinces the family to go to Mexico to find the Ahuizotl
. There, they encounter an almost entirely eyeless village - all the result of sacrifices to the Ahuizotl - and Doc and Drew meet their old rivals Miranda Grey and Deadbolt.
30: Into the Mouth of Darkness
The Saturdays decide to try cure Zak of his Kur power by finding the Epic of Gilgamesh, which details important information to do so. However, an accident sends them to Australia where gremlin-like bunyips annoy them and Zak finds it difficult to hide his pact with Argost. Meanwhile Doyle, Zon, and Van Rook search for supervillain Baron Finster, who knows a thing or two about Argost's past.
31: The Legion of Garuda
After recovering the Epic of Gilgamesh from a Viking tomb, the Saturdays travel to India to meet a secret society of sorcerers called the Legion of Garuda. The order's leader Gokul will need the Flute to Gilgamesh to perform the magic to destroy Kur, but their enemies, the Nagas, stole it centuries ago. Unfortunately, the ritual may actually become fatal for Zak.
32: The Return of Tsul 'Kalu
The Saturdays return to the ruins of their home (destroyed at the end of Season 1) to retrieve tomes from what's left of Drew's library. However, the Cherokee spirit, Tsul 'Kalu
, has appeared at the base to get his hand back from Zak's Claw. Meanwhile, Doyle, Zon, and Van Rook are at a Moroccan black market for cryptids where they are ambushed by Argost, Abby, and Munya; both teams after an ape-like cryptid.
33: The Unblinking Eye
Epsilon and Francis want to take Zak in and train his powers, but Zak would rather take his mind off the Kur problem with a good old monster hunt. So the Saturdays go to Turkey to subdue the Lake Van Monster
. However, Epsilon and Francis remain in pursuit as they have Nagas' Kur-detecting relic and are using it to track Zak's every move.
34: Life in the Underground
On Zak's twelfth birthday, Ulraj and Wadi arrive to join the celebration, but a large herd of various cryptid species has appeared in a nearby town unexpectedly. Argost is there too and he warns Zak that the cryptids are sensing Kur's presence. It is not loyalty to their god that drives them to congregate though, but fear of the upcoming new age.
35: And Your Enemies Closer
Having previously given Zak a neuro-parasite to telepathically communicate with him, Argost uses it to render Zak unconscious and capture him. Meanwhile, Doyle and Van Rook meet with Drew and the Tibetan monks who cared for her as an orphan to reveal the secret of Argost's identity. In the meantime, Zak finds that Argost has learned about Zak Monday and the Flute of Gilgamesh.
36: War of the Cryptids
In the series finale, Argost has absorbed Zak Monday's cryptid-controlling powers using the Flute of Gilgamesh and is now leading an army of cryptids against the world. While the allies the Saturdays have made over their adventures fight back, the Saturdays, Doyle, Van Rook, and the Secret Scientists infiltrate Argost's base again and to help Zak fight Argost and the Nagas. The final battle has begun!