The Secret Saturdays, on Cartoon Network
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The main character is 11-year-old Zak Saturday. He goes along on adventures with his parents, though they do seem less than thrilled about putting him in harm's way. Anyway, they're cryptozoologists, studying cryptids, which are animals the existence of which normal science has yet to accept. I'm sure you've heard of some of the more famous ones, but there are plenty of lesser-known ones out there. And I'm assuming some have been made up for this series (though I could be wrong). Anyway, Zak's parents are just two members of a larger group of "secret scientists," each of whom have a different field of study, though many, if not all, of these fields might be considered somewhat paranormal. Anyway, Zak's dad, Solomon "Doc" Saturday, is an inventor, who's created all sorts of amazing gadgets. His mom, Drew, was raised by gypsies, I guess, and is more supernaturally inclined than Doc. When she was a child, she got separated from her family and found by Tibetan monks or something. And Zak... well, he has some sort of power to control cryptids. He also has something called "the claw," a short staff with a grappling hook, which also amplifies his powers.
Eleven years ago, Doc and Drew discovered the Kur Stone, which could lead a person to a cryptid called Kur, and whoever finds Kur could, like, raise a cryptid army and rule the world. Some guy named V.V. Argost stole the stone, but a team of secret scientists retrieved it, and it was broken into three pieces, each of which was kept by a different scientist. Doc and Drew had one of the pieces. And as the series starts, eleven years later, Argost (the host of a show called Weirdworld, of which Zak is a fan), manages to steal back two of the pieces, and now he's going after the final piece. It's up to the Saturdays to stop him. But not every episode is going to be about Argost and Kur and all that, the Saturdays have plenty of unrelated adventures.
Anyway, the Saturdays have a komodo dragon (who is simply called Komodo) that can turn invisible, and a gorilla-cat named Fiskerton, who sort of talks (slightly less intelligibly than Scooby Doo). Also, they get a pterodactyl named Zon. All these creatures help out somewhat, but also tend to get in trouble along with Zak. Oh, and there are other villains. Argost has a mostrous manservant named Munya, plus there's a rival cryptozoologist/mercenary named Leonidas Van Rook (and his sidekick Doyle), who has a bunch of high tech gadgets of his own. Sometimes Van Rook works for Argost, but he's really only interested in money. Doyle, on the other hand... well, here's a spoiler for you: he turns out not to be such a bad guy, and later even turns out to be Drew's long lost brother, and joins the Saturdays in their fight against Argost.
I want to mention that at one point, the information available to me about seasons suggested season 1 ended with "Cryptid vs. Cryptid" and season 2 started with "The Underworld Bride." However, with no explanation that I'm aware of, it was later decided to call everything up through "Kur Rising" as part of season 1, and say that season 2 started with "Kur (part 1)." But I personally still consider that the start of season 3. Not that what I think matters, of course. Whatever, over the course of the series, we meet various allies and enemies of the Saturdays, and sometimes allegiances even change. And not all allies seem to be directly involved with the secret scientists. There's a girl named Wadi who becomes friends (and potentially more) with Zak. There's a secret scientist named Miranda Grey, but we also meet her sister Abbey, and she... well, I shouldn't spoil anything about her. There's an underworld city where an aquatic race called the Kumari live, and the prince of the city, Ulraj, becomes an ally of the Saturdays. There's also a family from a "mirror universe," who look like the Saturdays, but they're evil (a la Star Trek). Zak refers to them as the "Mondays." And the Saturdays eventually encounter a race of serpent people called Nagas (led by Rani Nagi), who want Kur to take over the world and eliminate the human race. And... I'm leaving out lots of other characters.
Also in (what I consider) season 2, we learn more about Fiskerton's true nature, as well as Zak's. I won't spoil that, but it's very important, and it makes for some big changes in (what I consider) season 3. I don't want to give anything away about that, but I'll say the season ends in a very cool way. And I think that's the end of the series (though that could change). It's a good ending, but there's still room for stories to tell in the future, so we'll see.... Anyway, the show can be amusing, often a bit silly and cartoonish, but it can also be quite serious and dramatic. Some things actually seem more realistic than your average cartoon. Not sure what else to say, but it's definitely a good show....