First story! Possibly my only, I just really wanted to write this! I rarely get inspiration, so please enjoy!

After an experiment caused by Mayuri Kurotsuchi, most of the Gotei 13's captains have been turned into children! What horrors will ensue? And can he create a cure before it's too late? Takes place before the Rescue Arc. Has Ichimaru, Aizen, and Tousen in it. Very mild language.

Oh, and I don't own Bleach.

The Experiment

Chapter 1: How It Began

Day 1

"Quick, Nemu! You useless swine, where is it? I'll be late!" Mayuri Kurotsuchi was getting impatient. After all of this research, all of this preparation, too! His guinea pigs were within reach, and his experiment still needed final touches!

"Here, Master." Nemu handed her captain the vial.

Kurotsuchi swept off without another word.

Once again, Kurotsuchi was impatient. Yamamoto was speaking in his slow voice about strange hollow attacks or whatever. Kurotsuchi knew he should be paying attention, that these hollows would likely become his next pet project, but God damn it, how was he supposed to concentrate when he was on the brink of a scientific breakthrough? With that thought, Kurotsuchi cleared his throat.

"Ahem."

Twelve sets of surprised eyes turned on him. What swine. He detested them all in one way or another. Kuchiki, for his condescension. Unohana, for "saving the lives" of his experiments, charmingly referred to by her as "victims." And Zaraki…what can you say about an oaf? Kurotsuchi had to admit, though, he did admire the certain je ne sais quoi about Zaraki. Something about his sadism, love of violence, and altogether madness rolled together into a signature eau de Zaraki that appealed to him. Regardless, Kurotsuchi didn't fear any of them. He continued, undeterred.

"I apologize for this interruption, Head Captain Yamamoto." Kurotsuchi began. Although he didn't want to, Kurotsuchi needed to act polite in the presence of Yamamoto. It may save his life in the chaos sure to follow.

"Setting aside for a moment these attacks, which are surely an important matter requiring the intelligence of each and every captain of the Gotei 13, I am giving you all an invitation."

Surprise and vague curiosity turned to suspicion. Pity, they've learned of his tricks. No matter. Not much they can do to stop him.

"Captain Kurotsuchi, we don't-" began Sosuke Aizen.

"An invitation for discovery. A chance to open the door to a level of science you never dreamed existed." Kurotsuchi pressed onward, pretending for the sake of his speech that the captain's interruption had instead gone along the lines of "Invitation? For what?".

"Look, we don't want to participate in another one of your experiments. Head Captain, I apologize, but I'm leaving for my safety's sake." Komamura said gruffly, moving for the door. It was sealed shut. He began to frantically beat on the door, other captains moving to help. Byakuya Kuchiki released Senbonzakura, to no avail. Not that anything could break down that door. It was sealed from the outside by Nemu, and she would only open it on his command.

"Captain Kurot-" Yamamoto began to reprimand him, but Kurotsuchi wasn't going to let him finish. Springing towards the head captain, he sprayed Yamamoto in the face with a purplish mist, immediately causing him to fall unconscious. He turned and quickly did the same to Yamamoto's ever-present lieutenant, Sasakibe.

"Now that I have your attention." Kurotsuchi said, reaching into his shihakusho's sleeve. He pulled out his creation, and set it on the ground in the middle of the room. All eyes turned towards it. Kurotsuchi quickly injected himself with a syringe, and pressed a button on the device. And all was chaos.

I promise the chapters will get longer.