"Yes," John agreed, "Yes we do. But since we are running out of that, would you care to explain?"

The Doctor turned to look worriedly into John's eyes, then glancing at the others'. "Clara, you've met them briefly before," he said, "The Weeping Angels."

The Doctor began to scan the walls, floor and air, while constantly looking around. "They're called Weeping Angels. I think they're behind this. They have to be. They can only move if you don't look at them and they're impossibly fast. They touch you and send you back in time, feeding off your time energy," he explained.

"Oh my God," John said, "Oh my God. How do you kill this thing?"

"You can't. You can trap it by looking at it or by making them look at each other but you can't kill them," the Doctor replied.

"I think you should see this," Sherlock said, his voice raised.

They all turned to see the lone Weeping Angel that appeared at the door they were walking toward.

"Doctor, you got a plan?" Clara asked.

"Yeah- RUN!" the Doctor yelled.

The three of them turned to run toward the entrance while the Doctor kept looking at the Angel and stepping backward as fast as he could without losing his balance.

"Wait!" John said, halting his run.

"What?" Clara asked hurriedly, "We have to go!"

"The floor moves, doesn't it? We aren't going anywhere, are we?" John asked.

The three of them had stopped running, and the Doctor caught up to them. Not knowing they stopped running and having turned his back on them to watch the Angel, he fell down when he bumped into John.

"Look at it! Now!" the Doctor screamed as he struggled to find his balance again.

They turned to the Angel that had moved a good distance. It now stood a mere ten metres from the four of them. It bared its teeth, its hands raised in a claw-like manner. John couldn't help but let out a scream.

"John, calm down. The Angel being here has stopped the floor from moving. The Angel cannot move when we're looking at it, remember? So the floor can't as well. The marking I made – it's now near the Angel," Sherlock explained.

"Genius!" the Doctor exclaimed happily.

"So how's about running?" Clara asked, wondering if they had forgotten their place.

Just then, the lights flickered and the Angel got closer.

They started running again, the Doctor and Sherlock always keeping an eye on the Angel.

"I should have mentioned, it can control lights, make them flicker!" the Doctor said.

John pulled a flashlight out of his pocket. "I've got a flashlight!" he informed.

"Why did you carry a flashlight?" Sherlock questioned.

"In case!" he said as he pointed it at the Angel.

The lights flickered, and so did the light on the flashlight.

"It won't work, it can control all lights," the Doctor explained.

The Angel got closer, and closer. It slowed down as it got closer, though, enjoying it. The Doctor could even make out the sound of its laugh.

"Can it see in the dark, then?" Sherlock asked.

"Of course it can!" the Doctor replied.

Sherlock looked for his mirror in his pocket. He carried it around always in case he had to see (or spy on) something or someone that's behind him. He fumbled around for a minute to find it and when he did, he pointed it in the general direction of the Angel, but it was right in front of him.

"Oh my God, Sherlock," John said, hope draining from his voice.

I hope this works. He made the Angel look at itself, and it stopped. The light stayed on. He backed away from it warily.

"Don't let me hit anything!" Sherlock warned.

"Don't worry Sherlock, you're just about at the entrance now, the door is open for you," John informed in the most normal voice he could muster.

Then, they were out.

"Don't stop making it look at itself, the door doesn't have a lock," the Doctor said.

They were back on the sandy ground, but it was already night time.

"We weren't in there for very long, were we?" Clara asked.

"No, time must pass slower in the building than out here," the Doctor explained, "But why was there only one Weeping Angel?"

"They must have worked out a system. To avoid looking at each other, you know," Sherlock guessed.

"That means…" Clara started, and the group of Weeping Angels that appeared in front of them finished her sentence.