Last April, Batman writer Scott Snyder stumbled upon a mystery of multiversal proportions: In the picture books for kids published by HarperCollins (but written and illustrated by a variety of creators), the same two characters -- one guy with brown hair and sideburns, the other with red hair, glasses and a soul patch -- show up in virtually every story. They're usually the cops that show up to haul the bad guys off to jail, but start flipping through those books and you'll see them as park rangers, bystanders, socialites and even villainous henchmen, always together and always hanging out in the background. So just what the heck is their deal?

To help solve the mystery, ComicsAlliance's crack research team (by which I mean CA Editor Caleb Goellner, a camera and a nearby bookstore) has compiled what we believe to be a fairly definitive index of the Kids' Book Cops. Check out their strange, inexplicable adventures after the cut!One of the first shots that Snyder posted last year came from the I Can Read! series' I Am Superman, in which Sideburns and Red appeared as Metropolis cops to help in apprehending Lex Luthor:

The HarperCollins version of the DC Universe seems to have pretty lax restrictions on jurisdiction, however, because they can also be spotted in Gotham City, helping Batman as part of the GCPD, as seen in Fright Club:

And in Gotham's Vilains Unleashed (note the completely different art style!):

They investigate the scene of Killer Croc's crimes in Reptile Rampage:

They even show up in Batman Versus Bane, a kid-friendly tie-in to The Dark Knight Rises:

Now, here's where things get tricky: Not content with DC's Gotham City and Metropolis, they also show up in Marvel's New York, usually helping out Spider-Man. Here they are in Spider-Man versus Hydro Man, trying to figure out how to clean up after a cement-filled super-villain battle:

And here they are apprehending Eddie Brock in the pages of Spider-Man Versus Venom:

Flying in the police helicopter in Spider-Man Versus Electro:

Cuffing the Vulture in the imaginatively titled Spider-Man Versus the Vulture:

And, in what is probably my favorite shot of the pair, being completely mystified by what they're supposed to do when a spider-themed luchador beats up a dude made of sand by turning him into glass in The Sandman Strikes:

With so many collars under their belt, it's no wonder they get all smug during Battle Against Doc Ock:

But while policework seems to be their primary occupation, it's not the only thing these two do in these books. In Going Ape, they show up as a pair of Gotham City zookeepers that are threatened by Gorilla Grodd before Batman and Superman show up to intervene:

In The Toxic Terror, they're park rangers who run afoul of Poison Ivy:

They're innocent bystanders in Escape From the Phantom Zone:

And in I Am Bane, another Dark Knight Rises tie-in:

And in Superman Versus Bizarro, where Red is apparently pretty miffed that his pal got so caught up in the Daily Planet that he's late for their meeting. Also, I think Superman is starting to suspect that something's not quite right with these two. Also also, I'm pretty sure that's Queen Elizabeth II:

They show up at a high-society gala alongside such bigshots as billionaire industrialist Bruce Wayne in the pages of Meet The Super-Heroes:

And they even swap out their police uniforms and tuxedoes for a life of crime as two Bad Dudes-lookin' thugs who try to ransack the Batcave itself in Dawn of the Dynamic Duo:

With all that going on, you can see why they'd head to the airport for a vacation in Spider-Man Versus the Lizard:

So just what is going on with these guys? Is HarperCollins trying to create a spin-off? Are they subtly teaching kids pattern recognition skills? Are they, as doubtful as it might seem, sowing the seeds of a massive, world-shaking crossover in their line of young readers' titles?

We have no idea. But we do know that these two are no longer limited to kids' books. As reported by iFanboy, they crossed over last year into the actual DC Universe with Gates of Gotham #2...

...a comic drawn by Trevor McCarthy and co-written by Kyle Higgins and Scott Snyder. Considering that that comic was set in the 1870s, these guys could show up anywhere. Keep watching the backgrounds for those unfortunate facial hair choices!

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