AHA! Double update. Told ya, didn't I? Enjoy!
The beings were translucent, with greying skin. The light shone through them, illuminating the blue veins that ran through their bodies. Although they were humanoid, there were no bones visible beneath their flesh, and yet they stood strong and tall, with nothing but a smooth, featureless surface where their faces should have been.
A previously unseen crease in what would be a human's left shoulder opened and as one, the creatures spoke in a jarring symphony of high-pitched screeches.
"Humans are escaping! Rebellious prisoners must be obliterated!"
The group of two humans, one questionable human and one definitely non-human backed up. The aforementioned questionable human turned to John.
"John- you're given to irrational emotions. If you feel inclined, I'll allow you to panic."
"That's very gracious, Sherlock," John returned sarcastically, and was rewarded with a smirk.
"We'll call it your birthday present, shall we?"
"Now now, come on! You boys... Or indeed, you girls... Or potentially multi gendered... Wouldn't want to be too hasty now, would you? Killing us would be a huge waste... Because... Because..." The Doctor looked pointedly at Sherlock. Rory saw his look and decided to step in.
"Because you can't experiment on us if we're dead!" he exclaimed.
"Rory!" The Doctor said with surprise. "Shut up!"
Rory looked wounded, but shut up. The aliens spoke again.
"We have no need to experiment. We know more of the human race than they could ever know."
Sherlock snapped into full Sherlock Mode, striding forward confidently.
"Then why take us prisoner?" he demanded. "What could you need us for?"
In response to his proximity, the creature in front raised his 'hand'. A beam of silver light flooded from the palm and slammed into Sherlock, directly into his chest. He flew back, crashing into the wall and sliding down beside John.
"Jesus, Sherlock!" he exclaimed.
The Doctor ran straight over to Sherlock, and scanned him with the Sonic. "Don't worry John. He's fine. He's just out cold. Don't complain, bit of peace and quiet!" he said cheerfully. "Now, as my friend here asked, why take us prisoner?"
"We are Guardians. You have arrived on our planet unannounced. This will not go unpunished."
"Guardians?" Rory repeated, confused.
"Uh... A bit like immigration," the Doctor said, passing the Sonic Screwdriver from one hand to the other nervously. "But a lot less nice," he added darkly.
"Oh. So is that bad then, Doctor?" Rory asked, voice thick with nerves.
"Well, it could be better, but it could be worse." The Doctor said.
"How exactly, Doctor?" Rory asked.
"Well, we're not dead, but we are captive and the people keeping us captive are crazy ghosty people who can zap you with their hands. Also, Sherlock's a bit unconscious. John, any sign of him coming around yet?" The Doctor asked.
"I think so, he's flickered his eyelids a bit." John replied, trying to keep the panic out of his voice.
"What are you going to do with us?" Rory asked, because it seemed nobody else was going to.
"Prisoners are executed," the 'ghosty people' chorused. "You are no exception."
Rory and John looked expectantly at The Doctor. "Doctor, I am not going to die before I find my wife." Rory said it as a statement; he was going to find Amy and there was no question of it.
"You have no say in this matter!" the aliens cried. "Execution is imminent!"
Together, they raised their hands. Swallowing his fear, John darted forward, his own hand outstretched.
"Wait! Please! If this is the last thing I say, I want to say it!"
"You threaten us?" the aliens roared, and John realised his outstretched palm could be construed as an insulting gesture, given where the aliens' weaponry was placed. He dropped it quickly.
"No, no, sorry, I'm just a human, I'm unarmed. But let me speak."
"Make it quick," the aliens said, and now they sounded snappy.
"Temper, temper," came Sherlock's arrogant tone. He sounded weak, but John was relieved all the same.
"Ignore him," John said, and he realised his knees were shaking. "Guardians, please hear our side. We didn't come to this planet to move into your land. We aren't immigrants. My moronic friend and I-"
There came a mumbled, "Takes one to know one," from Sherlock, which John ignored.
"-Are just detectives, assisting these two gentlemen in their search for a missing woman. None of us knew of your planet until our investigation brought us here. We beg you for mercy."
"I never beg," Sherlock put in. Now certain he was alright, John kicked his leg backwards and caught the detective's leg. Sherlock didn't seem to notice, and John considered kicking harder, but decided he could wait until later and murder him instead. Provided they survived of course.
Miraculously, the aliens were lowering their hands.
"This woman you seek- is she a redhead?"
"Yes!" Rory interjected excitedly. "You've seen her?"
"She arrived on this planet with our enemy. We could not capture her for fear he would wipe us out. Perhaps we can form an alliance."
At this, the Doctor darted forward, looking jubilant. "Yes, yes! A nice, peaceful alliance! You brilliant, reasonable creatures, you! Let's have a chat, shall we? I don't suppose you've heard of Jammie Dodgers...?"
Sorry for errors, I'm really tired and my editing is not at its best. But review, pretty please? :).