Tenenbaum was hurriedly leading all of the former little sisters she had rescued to safety since Lamb had discovered their location, so she had to move them from the ticket booth they had been staying in. Subject delta had agreed to stay and fight off the splicers that had been sent by Lamb while she got all of the former little sisters to safety. Tenenbaum hurried all of the former little sisters as fast as she could just in case Delta wasn't able to hold all of the splicers off, and she lead them down a hallway away from what was sure to be a bloody fight. She could already hear the muffled mad ramblings of the splicers as they came closer. As she got the last of the little ones into the hallway she looked back as the last of the little ones had made it to the hallway, and she could see flashes of lighting and splicers screaming in agony as they were hit with electoral bolts and promptly killed by the raging Delta with a reeving drill.
Tenenbaum continued cautiously leading the little ones down the ominous hallway that ether held their escape from the splicers or certain death. Tenenbaum was thinking about what she would do if they came upon any splicers. She could take care one or two splicers with her revolver that she always kept with her, but she couldn't take on anymore and she certainly couldn't kill a spider splicer or Houdini splicer, and it was only a matter of time until they came upon one. That was when she was dragged back into reality by something tugging on her dress. It was a small blonde girl named Allie saying "Mama Tenenbaum what is that light up there". Tenenbaum caught a glimpse of the light the girl was talking about. The light was just out of sight because of a bend in the hallway. The light was blinking back and forth from a dull yellow to a bright green. Tenenbaum felt very uneasy about the light she then told all the little girls to hide in a room that they were beside while she went to see what the light was. Tenenbaum cautiously made her way around the turn in the hallway, and what she seen made her blood run cold.
The light was coming from the helmet of a big sister. The sight of the big sister made Tenenbaum freeze where she was. Her mind was telling her body to run to the former little sisters, but her body just froze. She couldn't even make herself take a breath of the stale dead air that occupied the inside of rapture. After a minute she started regaining control of her body with the terror that took it over starting to recede after what felt like an eternity. Tenenbaum noticed that the big sister had been trapped by rubble that had fallen from the ceiling. The rubble that was keeping the big sister trapped and would have killed any other living thing in rapture, but it had just been just enough to keep the big sister trapped. Seeing that it was trapped under the rubble Tenebaum ran back to the room the former little sisters were hiding out in. She got to the room she opened the door, and closed it as fast as she could with it still being quiet, so that it didn't attract any unwanted attention.
The former little sisters were inventively watching Tenenbaum as she paced back and forth thinking about what to do with great curiosity, and one of the girls with brown hair named Alexandria had finally become curious enough to ask what the light had been and why she was so terrified. "Mama Tenebaum; what was it, what was it." Alex eagerly asked. Tenenbaum replied "It was a big sister mein little one" trying to sound as calm as she could in the situation as to not to scare the little ones. Alex went and sat back down with the other former little sisters and they began eagerly discussing the big sister between themselves. They still slightly admired the big sisters since they hadn't completely been cured of the little sister conditioning yet. That was when the idea came into Tanenbaum's head that she might be able to cure the big sister and return her to being a normal teenage girl. She was thinking about how if they could get a big sister on their side they wouldn't have to worry about her and the little ones being attacked by a splicer or a rouge big daddy or even another big sister. Also a great guilt rested on her shoulders because of the big sisters. They were the little sisters that her and Jack hadn't been able to rescue during their escape from rapture, and they had grown and been turned into tools by lamb to kidnap more little girls from the surface to make more little sisters to keep the wheels of rapture turning.
She decided to get to work on the formula to turn the big sister back to normal. Luckily the room that they had decided to take refuge in looked like it had been a lab before the fall of Rapture. Tenenbaum spied some lab equipment that she could use to modify the plasmid she used to cure the little sisters to where it would hopefully work on the big sister. After a couple hours of working she finally finished with it. She told the former little sisters to hide in a closet that was in the room until she had returned, and she left them a radio in case she didn't return and she told to try to get in contact with Delta or Sinclair if she hadn't come back in a little while. With a couple hugs from the girls she left the relative safety of the room to go to the big sister.
She was making her way back to where the big sister was trapped under the rubble. She got within eyesight of the big sister and it was just lying there with no indication that it was alive except for the slow blinking of the helmet light and slight movement of its chest. Tenenbaum reluctantly moved closer and saw that the big sisters arms were trapped under the rubble. It made her feel a little calmer knowing that the big sister wouldn't be able to hurt her while she tried to cure it. To administer the formula to the big sister she would have to take her helmet off to get to exposed skin. So Tanenbaum bent down and reached for the helmet. She undid the latches that was holding the helmet in place then she hoisted the helmet up and with a hiss of air the helmet came off and exposed the big sisters head. The big sister had very pale skin looking as if it had never been exposed to the rays of the sun. She was a girl that looked between the ages of 17-19 with a tangled mess of brown hair that fell to her shoulders, and she had a predominant scar that ran across her face from her right temple down to the bottom of her right cheek.
Tenenbaum decided to go ahead and try the plasmid that she had made up to see if it would cure the girl. She reached forward and touched the face of the girl and there was a flash. Tenenbaum jumped back just as the big sister opened her yellow eyes and let out an ungodly screech. The girl went to struggling and was able to dislodge herself from under the rubble that she had been stuck under. Tenenbaum noticed that the big sisters skin seemed to have a red glowing tint to it, and thought that the plasmid must've not really had an effect. She turned around to run from the big sister, but she only got a few feet before the big sister had jumped at her and pinned her against the wall with one of its' hands pressed against her shoulder and raised its' arm with the large Adam needle attached to it and pressed the needle up to her neck. Tenenbaum had her eyes closed waiting for the cold needle to stick into her neck and end her life, but there was another flash and she looked up to see what had happened and she watch she saw wasn't the dull yellow eyes of a big sister staring at her, but the emerald green eyes of a teenage girl.