Disclaimer: I don't own Bones or anything from Doctor Who.
"Almost every species in the universe has an irrational fear of the dark, but they're wrong, because it's not irrational. It's Vashta Nerada."
"What's Vashta Nerada?"
"It's what's in the dark. It's what's always in the dark..."
The victim had been discovered by a park ranger earlier that afternoon. A driver license found on the body identified the remains as those of a hiker who'd been reported missing three days ago. The man's clothes had been ripped to shreds, suggesting a violent attack. There was no indication, however, of who or what had been responsible.
Brennan squinted against the specks of dust hovering in the rapidly fading sunlight as she studied the victim's remains up close. Something wasn't right here. The flesh had been completely stripped from the victim's bones, but the bones themselves appeared to have been left untouched. Nothing was broken or missing. There were no signs of decomposition or mutilation. There were no bite marks from scavenging animals. No cut marks from blades or surgical instruments. No burn marks from fires or chemicals. No trauma of any kind. It was as if all the soft tissue had spontaneously vanished, leaving only the bones and clothes behind.
Brennan's eyes drifted downwards as something else caught her attention: A scrap of crinkled paper lying on the ground next to the victim. She picked it up and unfolded it.
Booth looked over her shoulder. "What've you got there, Bones?" he asked.
"Something the victim wrote, I think," Brennan replied, handing him the paper. "I'm not sure what it means, though." Finished with her examination, she stood up. "I can't find the cause of death," she said. "We need to take these remains back to the lab for further analysis."
Booth nodded. "Better hurry," he said, glancing around. "It's getting pretty dark out here. Wouldn't want to be lost in these woods."
As they headed back to their car, Booth looked at the wrinkled paper Brennan had given him. Written on it were three hastily scrawled words:
COUNT THE SHADOWS
"...This is not a shadow. It's a swarm. A man-eating swarm. The piranhas of the air. The Vashta Nerada. Literally, the shadows that melt the flesh. Most planets have them but usually in small clusters..."
"What do you mean, most planets? Not Earth?"
"Mmm, Earth, and a billion other worlds. Where there's meat, there's Vashta Nerada. You can see them sometimes if you look. The dust in sunbeams."
"If they were on Earth, we'd know."
"Nah. Normally they live on roadkill. But sometimes people go missing. Not everyone comes back out of the dark..."