How did one break into prison?

Turns out it's simple enough. Just walk up to the first guard you see and surrender.

The Stormcage Guard were men—at least, they looked like men—in black suits and tinted helmets. To Rory they looked like a corps of motorcycle cops, and they all had big black guns. Really big, really black guns.

One of the guards was approaching the TARDIS, though Rory doubted the ship was particularly visible through the rain and the dark. Amy glanced up at Rory, then marched right up to the dark figure.

"Oy," she said. "Who's in charge around here?"

The guard froze. It processed Amy for a moment. Then it pointed the gun at her.

"Amy!" Rory yelled. He pushed her aside—

And found himself face-to-face with the business end of the biggest weapon he'd ever seen in his life. A line of red text appeared across the front of the helmet. YOUR ENTRY IS UNAUTHORIZED, it read. Then it emitted a burst of static.

Three other guards walking the yard froze, turned, and walked in tandem toward Amy and Rory. Slowly. Inexorably. Mechanically. Across each helmet glowed the words YOUR ENTRY IS UNAUTHORIZED.

"They're robots," Rory murmured.

Amy blanched, then glared at the nearest guard. "Unauthorized, eh?" she said ferociously. "And whose fault is that, d' you think? Falling down on the job a bit, aren't you?"

"Amy," Rory whispered. "What are you doing?"

The guards were getting closer. They lifted their guns and took aim.

"Improvising," Amy whispered back. She turned back to the guard. "I'm Mrs. Williams," she declared. "Inspector from the Ministry of… um, Prisons and Jails. And I demand to be taken to you leader. Right now. Rory, show 'em."

"Show them what?" said Rory.

"Our identification."

"It doesn't work."

She did not look away from the robot guard. "Just try it."

"All right," said Rory. With shaking hands, he flipped open the psychic paper and shoved it in the guard's face. "Take that."

YOUR ENTRY IS UNAUTHORIZED, said the guard.

Rory and Amy exchanged a glance.

YOUR ENTRY IS

Then it stopped. Just stopped. Like someone had shut it off.

Rory glared at the mechanical soldier. Then he pivoted, showing the paper to the gathering army. The approaching guards stopped in their tracks.

A moment later, all four of them lowered their weapons.

Their helmets went blank.

Rory looked at the paper. He didn't see anything at all. Just a sheet of paper.

Interesting.

"Y—Yeah," said Rory. "What she said. And then some. We're inspectors." He tucked the psychic paper into back pocket of his jeans. Crossed his arms and stood tall. "And when we get back to headquarters," said Rory, warming to his role, "I'm going to file a very sharp report on you lot. Very sharp indeed. Especially you." He pointed at the one Amy had approached.

New words coalesced on the round helmet.

YOU WILL FOLLOW.

"Rory," said Amy. She rested a hand on his arm.

"You call that guarding? You know what I call it? Rubbish, that's what."

YOU WILL FOLLOW, read the helmet.

"Rory, I think we're in."

"Oh," said Rory. He lowered his finger. "Right."

The guard pivoted and began a slow march. The back of the helmet said: YOU WILL FOLLOW. The other guards fell in behind them, guns held at the ready. Rory couldn't tell if they were being led somewhere as guests, or taken prisoner. A pernicious doubt churned in his stomach. But at least they were moving forward.

The walls of Stormcage loomed. Amy took one last longing look at the TARDIS.

Its blue walls were shrouded by rain and shadow; its light gone out.