Under the city hospital of Mitakihara City, there is a secret lab that belongs to a shady corporation that creates bioweapons for the military market. This corporation is called Umbrella.
"Did you finish that report yet?" one scientist asked another.
"Yeah, I did. The one on the T-Virus effect on the giant squid?" the other scientist answered.
"Good, we need to have the BOW ready by next month or we'll be the next guinea pigs!" the first scientist said worriedly.
Meanwhile, at Mitakihara Middle School, there is a career fair, trying to get the students interested in different fields.
"Look, Sayaka, that booth over there is for a boutique store!" Madoka pointed out to her best friend Sayaka. She thought it looked pretty.
"Oh, the flowers are so cute!" Sayaka exclaimed.
Madoka pulled Sayaka to the booth and while they were admiring the flowers, the school intercom announced that the sponsors of the day, the Umbrella Corporation, were about to start their presentation in the Gym and everyone should go there.
As Madoka and Sayaka were heading to the Gym, they ran into Mami who joined them.
"Hi Madoka, hi Sayaka!" Mami greeted them warmly.
"Hi Mami!" Sayaka and Madoka both said at the same time.
They started laughing with each other.
When they got to the Gym, an Umbrella Corporation representative went up to the stage and began to talk.
"Hello students of Mitakihara, I am a representative of your sponsoring organization, the Umbrella Corporation."
He waited for applause.
"We have many volunteer opportunities at our Mitakihara facilities, you may have seen our chemical plant near the harbor. We are now looking for volunteers to help take on custodial positions. It would look great on a resume," the representative continued.
The talk went on for a while and just became a big advertisement for Umbrella medical and cosmetic products.
"Madoka, let's go buy that new Umbrella brand conditioner and see if it really works wonders!" Sayaka suggested to Madoka.
"What do you think, Mami?" Madoka asked Mami.
"I think it's a good idea," Mami agreed.
The trio decided to go to Umbrella's local store. They walked in the door, as they did a bell hooked to the door rang alerting everyone to their presence.
"Welcome to Umbrella Pharma and Cosmetics Mitakihara Store, how can I help you?" a door greeter said welcomingly as he ran over to them.
The trio awkwardly waved to the greeter and kept going. They turned a corner and went into the conditioner aisle. Sayaka scanned up and down the shelves whilst Mami and Madoka looked at the first display they saw. Sayaka started pulling products off the shelf looking for the latest and greatest one.
"Over here you two! I found it!" Sayaka exclaimed excitedly to Mami and Madoka.
"Oh, that's wonderful Sayaka," Mami responded, rushing over to her side. She took the bottle and examined it.
"What do you think?" Madoka probed Mami.
"Oh I think it will be great!" Mami replied to Madoka.
The trio made their way to the register where the cashier was nowhere to be seen. They leaned past the counter trying to see into the backroom. Mami noticed struggling noises coming from the back and decided to investigate. Mami hopped over the counter with her soul gem ready to transform. When she turned the corner into the backroom she shrieked and ran back out terrified.
"Mami what's wrong?" Sayaka asked in confusion.
But Mami just ran past her and pushed outside the door only to rush back inside again even more panicked.
Mami was just terrified, unable to speak. Whatever she had just seen was traumatic enough to shut her up and she had seen all sorts of things while fighting witches. Then a decapitated head was launched out of the backroom and hit the wall behind the counter making a wet splat sound.
The trio turned and stared at the bloody mark left on the wall and slowly glanced towards the door to the backroom as the cashier walked out, except, he had blood on him, his gaze was now expressionless and he was holding another person's corpse in one hand. The cashier turned over to face the three and in a fit of what can only be described as bloodthirst lunged over the counter missing Madoka's foot by an inch. Sayaka backed away and shrieked. Sayaka grabbed a display and threw it on the zombified cashier.
"What the hell was that!" Sayaka shouted in dismay.
Mami finally got ahold of herself and transformed into her mahou-shoujo form.
"Madoka, Sayaka, we have to be careful, I don't know what that was but it wasn't like any witch I've seen," Mami explained.
"Where's Kyubey when you need him? I wish I could be a mahou-shoujo right now to survive this," Sayaka said in jest. The trio looked around the building for anything Sayaka and Madoka could use to defend themselves. Madoka was in shock and on the verge of tears.