Teenage Mutant Samurai Wombats

A common western action cartoon format that was very popular in the 1980s and 1990s (after the success of Teenage Mutant Ninja Turtles spawned a crop of imitators) and still continues to this day.

The format is more or less this: A team of heroic monsters (aliens, mutants, or magical beings) are somehow created, awakened, or arrived in the modern world. Usually a modern American city. They are honorable creatures who set out to fight crime. The average person fears them for their appearance, and they must hide from Muggles. However, they befriend one or two open-minded humans, usually either children or career women. These women or children end up being the team's friends and guides to modern Earth, and are Secret Keepers, and may also be the Kid with the Leash. Together, they all fight supervillains and evil creatures in a City of Adventure.

Since these shows are usually aimed at young boys, expect The Smurfette Principle to be in full swing. The heroes are usually The Last Of Their Kind, with no females. Consequently, Interspecies Romance will usually be explored, particularly by fans, especially if the Secret Keeper is a career woman.

The Secret Keeper will often be hiding them in the beginning, but since the monstrous team is usually a Five-Man Band or Power Trio, they usually get their own headquarters. It's a good thing that Abandoned Warehouse/office building/ornate palace was around!

These series tend to be Merchandise-Driven.

Not to be confused with Ninja Pirate Zombie Robot, though the Rule of Cool often plays a role.

Examples of Teenage Mutant Samurai Wombats include:

Anime and Manga

The Japanese Microman anime.
This was actually the format for Sonic X, with Sonic and his Furry pals as the "monsters" (albeit cute ones) and the Thorndyke family as their human allies. This was ostensibly to give the audience a human identification character—Chris. They quickly dropped The Masquerade though, and Sonic became an instant celebrity.

Comic Books

Teenage Mutant Ninja Turtles -- which started out as a black-and-white independent comic in the middle 1980s -- is the Trope Codifier, of course—with April O'Neil and Casey Jones as the human allies.
- As well as the many other anthropomorphic animal superhero comics which were "inspired" by them.
  - Ironically, the Ninja Turtles were originally intended as a parody of Frank Miller's gritty style (Ronin and Daredevil being his two notable works to that point and the two books most closely parodied). They spawned a bunch of "adjective, adjective, adjective, noun" anthropomorphic imitations/parodies. But those were mostly dreamed up by fans and wannabe pros looking to cash in (TMNT #1 was very rare and up to $2–300 in demand). This didn't stop until it crashed the comic market in the famous "black and white implosion" (which was a dry run for the Dork Age market collapse).
- Making Adolescent Radioactive Black Belt Hamsters a parody of a parody.
Going way, way back, the original X-Men basically started off this way, minus the pet human.
Conversational Troping in an early-90s issue of Green Lantern set at a toy expo: "Buddy, every ten minutes I've got someone trying to sell me 'the new Turtles'. I've a warehouse full of stupid dinosaurs named after dead presidents!"

Live-Action TV

Often parodied on Late Night With Conan O'Brien, where Conan's mock fall previews often feature programs such as Embryonic Rockabilly Polka-Dotted Fighter Pilots or Country Cuckoo-Clock Codpiece Zulu Warriors.
Non-cartoon example: Beauty and The Beast.
The live-action show Dark Angel was similar in premise, with the exception that most of the Chimera could at least pass for human (with the notable exception of Joshua in season 2). Nevertheless, Logan acted as a Secret Keeper for Max and the rest.

Video Games

The Battletoads from the videogame of the same name.
Parodied in the old adventure game The Big Red Adventure. One TV showed the "Teenage Mutant Ninja Beetles", who were four cockroaches with the faces of the Fab Four!

Web Comics

Master of the subverted trope that it is, The Perry Bible Fellowship gives us this.

Western Animation

The original Transformers—with the Witwicky family as the human allies.
- Although the Autobots never really hid from anyone in the original series. They were acknowledged by the world's leaders as early as the end of the three-part pilot.
  - In the TV show, that is. In the comic, the world remained fearful of all Transformers, regardless of faction. The Autobots had a few reliable human allies like Buster Witwicky and G.B. Blackrock, but they were few and far between.
- Transformers Animated is more in line with this trope, featuring Sari as the kid, a smaller Five 'Bot Band, and an abandoned Detroit car factory as their HQ. The Autobots still don't hide from anyone, though.
- Played straight withTransformers Prime.
Gargoyles—with Elisa Maza as their human ally. Gargoyles was one of the few shows to acknowledge that a situation like this simply can't last forever, and slowly had the Gargoyles transition from complete secret, to urban myth, to publicly known... and feared.
Street Sharks—with a Surfer Dude as their human ally. (The Sharks themselves used to be human surfers as well... it's complicated.)
- Not to mention their spinoff series, Extreme Dinosaurs!—Just the title should do.
Mummies Alive Centuries old Mummies able to summon Power Armour, one of them a Sweet Polly ... Cleopatra?... Ride around in weird ancient Egyptian vehicles and got an Egyptian version of a boomerang whilst protecting a child reincarnation of an ancient Egyptian Pharaoh from an advisor of said Pharaoh.
Biker Mice From Mars—allied with Charley, a Wrench Wench mechanic whose garage they live in. One of them has a crush on her, as she reminds him of a girl back home.
Toxic Crusaders, the kid-friendly animated Spin-Off of the Toxic Avenger movies.
Dinosaucers, in which good and evil teams of evolved dinosaurs engage in more-or-less comic battles on modern day Earth. The good guys have a bunch of human teenagers as their Secret Keepers.
The Mighty Ducks cartoon, which may as well been called "Hockey-Playing Twentysomething Extraterrestrial Mallards". About a group of anthropomorphic ducks from a world surronded by puck-shaped asteroids where hockey is Serious Business (...you mean they're Canadian? *rimshot*) fighting space dragons and posing as a regular hockey team in modern-day California. No, really.
- To be fair, they 'pose' as a hockey team by actually playing hockey in a league. But they still fight space dragons and villains-of-the-week.
Aqua Teen Hunger Force spoofs this. (Or at least the title does.)
Parodied in Tiny Toon Adventures, in which Plucky is a fan of the "Immature Radioactive Samurai Slugs" franchise.
The initial Five Episode Pilot of Challenge of the Go Bots was like this. Since the Gobots' cover has been completely blown by the end of that Story Arc (it's not as if Leader-1 didn't try to observe the Obstructive Code of Conduct at first), subsequent episodes show the Guardians interacting with Earth's people and governments completely out in the open.
The 1993 series Stone Protectors attempted to market the troll doll craze to grade school boys. The heroes are an awful Fake Band from New York City who are transformed into troll-like super heroes by magical crystals, then have to protect the crystals from the Saurians, reptilian bad guys who would use their powers for evil. The problem of hiding the conflict from the public is averted because the heroes are quickly transported to the Magical Land where the crystals came from.
Adventures of the Gummi Bears might count... only it's pseudo-medieval instead of modern day, and it averts The Smurfette Principle.
Road Rovers.
Kung Fu Dino Posse, a 40-episode cartoon series that aired on Starz in 2009, is an homage to several Secret Mutant Hero Teams before it, including the Street Sharks spinoff Extreme Dinosaurs and TMNT. In modern times, a quirky science geek accidentally thaws out four anthropomorphic dinosaurs, whereupon they inflict inexplicable Kung Fu upon evil raptor villains and their army of generic mutants. The series is well aware of its own cliches and often leverages them for comic effect.