"Move over, techkie!" Yelled Everlyn as she took a few steps back and stormed in. She raised her leg and kicked towards the door, almost hitting the Doctor but breaked the door wide open. She dragged the two guys, now almost stunned, through the door, slammed it shut and used a chair as a blockade.
"Phew!" The Doctor stood up and gave Eva a pat on her shoulder, "nice moves, ninja girl!"
"I took karate lessons when I was 11," Everlyn was panting, but she had a smile on her face, "never practiced after that, but hey! The body remembers!"
"I am glad that I did not have to go through that..." Thinking about what could've happened if he was home during that time, Charlie couldn't help but shiver.

"What, you didn't live with her?" The Doctor was just about to go and check surroundings but stopped and turned around, "I thought you were twins?"
"It was complicated, " Everlyn shrugged, "they say that Charlie was too smart for regular school, so they took him for special training and stuff..."
"I didn't know the topic for our conversation had shifted onto me?" Charlie stopped the conversation abruptly, unlike his usual self.
"Oh, right, right... gotta check some defences..." the Doctor didn't say one more word, but he did look at the boy with some suspect. He looked up: there was a window on the top of the dome-shaped roof; through there, he could see the sun slowly setting. *We are almost out of time*, he thought.

Everlyn didn't want to follow up either. Her brother had never talked about his life at the institute, but it wasn't a good time to ask. Instead, she focused on another aspect, "But Doctor, what was happening just now? Why did we have to run?"
"There were some things that were chasing us. In the shadows..."
The sudden stop grabbed Everlyn's attention, "what is it?" Charlie pointed her to the ground.
On the floor, the shadows that were cast by the shelves are advancing onto them, like a swarm of shark closing in on their feast.

"Quick! Under the window!" The Doctor yelled as he pulled his sonic screwdriver and buzzed at the shadows, "this will buy us some time. Now, have you got a torch?"
"I've got a small one, if it will help!" Everlyn reached into her jacket and got a little flashlight. She threw it at the Doctor, who caught it then started to sonic it, "I am boosting its power! Now get under the window and ***stay out of each other's shadow!!!"***
The twins did so. Charlie looked around and found something useful, "there are some emergency lights over there!"
"Thanks, little cherry!!" The Doctor set the torch in his hand onto the ground, the light pointing out, "they are the Vashta Nerada. They live in the shadows and they eat you alive!!" He ran over to the emergency lights, boosted their power and set them on the ground the same wat he did with the little torch.

When all this was done, the shadows had stopped advancing in. The Doctor sat down on the floor, finally relaxing for a bit, "phew! That was close!"
But not a single moment later, the other door made a very loud noise. The trio turned to look, only to find two other people, also barging in. One of them was a man in a blue suit with a big brown overcoat, and the other was a middle-aged ginger woman wearing earth-looking cloth. They were rather surprised to see the trio.
The Doctor stood up with a big smile on his face, "now this, is, absolutely brilliant."
TBC

-----End of Ch.4-----