Author's Note: Hi everybody! I've always wanted to try writing out scenarios of different characters from different stories. I love crossover events and I thought it would be fun to throw in Kim Possible and Batman. Watched Kim Possible growing up and I always thought, would she really be able to take down big villains like the Joker? And do her fighting styles really match to actual trained superheroes? This is what this story is for. Hope you enjoy it! Be kind! First time doing a fanfiction. Thanks! First 2 chapters are setting up the story from Gotham and how they are able to crossover.

Gotham City

The Docks

1:24AM

It was a night like any other. Any sensible person would be sleeping soundly in their beds at this time of night. But this place was no ordinary city, it was Gotham. At night, crime reigns supreme and lunatics were setting plans in motion.

I however have made a vow. To watch over Gotham in these dark nights. To take care of criminals who in truth are superstitious and cowardly. To make sure the innocent continue sleeping soundly at night.

I am Batman.

Recently, in the underworld, there have been chatters about a new technological device going through the black market. Black Market deals happen all the time. Guns…Drugs…Advanced Tech…All kinds of contraband. Even a polar bear once… But this item was different. It was going to arrive at the docks soon. i've done stake outs here several times over the years. Tonight, it was on high alert. Must be something big. From the usual 20-30 guards for their deliveries, it's gone to nearly 3 times as many. Hmmpph…still not enough.

If my research is correct, this has something to do with the attack of a Cadmus labs' convoy last month. The report states one item was stolen when in transit to another facility. A highly advanced machine. There was no coverage of it on the news because the government didn't want to cause any panic to the public…or maybe they just don't want to look bad in the eyes of the people… They've been on red alert looking for their missing toy. This must be it…

"Father, are we going to stay here all night, or are we going to get work?"

"Not yet, Robin."

"Kid, don't get too excited, there's enough bad guys for the 3 of us." He's still checking for any more surprises."

"Hmmpph, you scared to jump into the fray? Maybe you can't handle this many Grayson, but this is simply child's play for me to take down this many chumps."

"Ehem. It's Nightwing. Or would you prefer, I call you Damien as well." No? Then keep it down."

"Quiet…both of you…something's happening."

A car just rolled in. It's nothing fancy in terms of vehicle choice but it's definitely the buyer since it stopped right in front of the shipment. Another guard is running towards the passenger door to open it but before he can reach the handle—-

Bam! The car door slams right into the thug's face. The impact makes the man fall down and roll over.

"Woops! My bad, my good fellow! I was just a bit too excited. That's all! Haha! I've been waiting for this all day. My brand new toy has arrived! Now the real fun can begin."

A serious mood came over Batman's entire body. The man who stepped out was no ordinary criminal. The one person who some may call the antithesis of the dark knight. The Harlequin of Hate, the Clown Prince of Crime…The Joker.

"This got a whole lot more serious…Why does it have to be him?…What's the next step, Bruce?" said Nightwing.

"Hmm…the plan doesn't change. We just have to make sure we take him out of the equation, fast. The Joker is unpredictable, who knows what he's got underneath his sleeves…literally."

—- Closer to the shipment—-

"Boss, your new toy has arrived! We also made sure to "pay" for the product just like you asked."

"Good job, I hope it wasn't tooooo expensive." said the Joker.

"No sir…They'll be 'sleeping' soundly with the deal we made."

Hmm…Hah!…Look at you, with a sense of humour, I like you already!" "But enough of the funnies, and show it to me already."

Everyone was tensely waiting to see what the fuss was about. What kind of device would make master criminals fight over and kill one another for? Surprisingly, it was only in a small case. It looked like a small cube. Alien in origin. It looked like the people of Cadmus tampered with it and added their own devices around it. Wires, and man-made technological flair which gave it this space age look. Batman realised then and there that he's seen one of these devices before.

A Mother Box.

"Not good."

"What is it, Father?"

"It's called a Mother Box, Robin. When travelling to New Genesis, the New Gods would use this device to travel anywhere throughout the stars. But it's not limited to teleportation. It's…alive. It has other uses such as energy transference, force field generating,… sensing danger,… and it can even take control of other technological devices."

"And in the hands of the Joker, who knows what he's got planned with it," Nightwing shuddered at the thought of what that madman would do as he replied.

"What's he doing now?" said Robin.

"He's holding onto it…and seems to be just looking at it..No, more like 'talking' to it." said Nightwing.

Suddenly, the Joker looks in the direction of where the trio of heroes were hiding in the darkness. Then gives a smile which gives shivers to anyone who sees it.

"Bruce, you did say something about having the ability to sense danger right?" Could it be that he's spotted us?"

Before Batman could start…gunfire rained down on the area the three of them were hiding.

"The party has started and we have three "party crashers", Take care of them boys!", the Joker laughed as he said.