Jenny heard footsteps on the tile floor and spun around. The creatures were back.

"Roland, get up slowly," she whispered. "Move to the center of the room."

The dark figures inched closer, stopping when they had blocked the path to the mirrors. Jenny faced the leader with one hand by her knife.

"You learn so quickly," the leader hissed. "Have you discovered what is

wrong?"

"Not yet," Jenny replied. "I don't quite understand how the machine works."

"You know what it is for. Surely figuring out how it operates is simple

enough."

"If it's so simple why can't you fix it?"

The leader grumbled softly to itself. "We have tried to fix it, but the portals remain the same. Nothing we do prevents them from harming living organisms."

Jenny was flustered by the creature's behavior. Nothing he said made any sense! If they wanted so badly to go through the portals, why not acquire a spacecraft to protect themselves? It was as if they cared more about repairing the machine than using it.

"Who are you?" she asked. "Why do you need the machine to be fixed?"

"We… are the Spectres. We cannot go through until the portals work

properly."

"What, are you superstitious or something?" Roland cut in. "The portal can't hurt you if you're shielded."

"Do not question us!" the Spectre shouted. "You know too much as it is. If you learn much more we will be forced to deal with you."

"This thing has an attitude problem," Roland whispered to Jenny. "Should we try to scare them off again?"

"No," Jenny replied. "That will just anger the leader. Wait until he's gotten something he wants."

"What would that be? We don't know how to fix it! We don't even know

how it works."

The lead Spectre had his head tilted as if he was listening in on their

conversation. He had not moved or interrupted them, which disturbed Jenny more than it encouraged her. She wondered what she could possibly know that the Spectre might need, and then she remembered the numbers on the control module.

"Zero four sixteen…" she mumbled, "nineteen forty‑two A."

A memory clicked in her mind and her eyes widened. "It's the date,"

Donna's voice echoed in her mind. "Oh! It's the New Byzantine calendar!" the Doctor shouted.

The Spectre noticed she had realized something and turned its head to look at her.

"Roland, what's the date?" Jenny asked out loud.

"The 25th day of July, 6012," he replied, somewhat confused.

"Or, possibly, zero‑seven, twenty‑five, sixty‑twelve, A," Jenny said. "The first half of the number string was the date. 'A' stood for 'Anno Domini'."

"What about the second half?"

"Possibly coordinates. Where would '51.5 North, 0.1 West' be?"

"Somewhere in London, I think."

"Then the first portal leads to London on the 16th of April, 1942."

"Wow," Roland breathed. "Not bad. How did you figure that out?"

"When encountered with strange numbers that you don't know the meaning of, check to see if it's a date."