After walking endlessly around London until around the time it was almost sunset, Grissom counted the beetles he had collected. Each of the beetles was a different size, the smaller ones were younger and the bigger ones were older. Grissom had nine total from his and the Doctor and Sherlock's trek. "Nine total," he told them. They nod. Grissom sighed, "This will have to do."
"I'm plenty curious about this theory of yours, Grissom," the Doctor looked at him. Sherlock nodded, "Indeed, what are you thinking?"
"Protocols," Grissom told them as he held the container under his arm.
They headed back to UNIT. Upon arrival, Grissom was immediately told in a hush-hush voice that something was waiting for him in his office. Grissom nodded and left for his office, leaving the Doctor and Sherlock to be taken by the guard toward where John and Clara were.
Grissom arrived to his office to see a birdcage sitting on the table against the wall. The raven silently pecked at the food provided for it as Grissom walked toward it. He studied it, indeed it didn't have amber eyes, and it was normal. Grissom sat the container of beetles down on his desk as he continued to look at the raven. He questioned why would the ravens be interested in the Plague Doctor, indeed the beetles would have them following him, but then it dawned on him that normally ravens wouldn't fly around in the pitch dark night. Grissom chewed on his lips as he pondered.
His attention turned to the beetles. "I'm a raven. I see a beetle. I'm hungry; I'm not a picky eater so I go after it. I eat the beetle, then what?" Grissom rubbed his beard. It stumped him for some time until Nick came with the test results and handed them to him. Grissom read the results as he sat at his desk, the amber substance was something UNIT never saw before, and in fact the lab technicians were unable to compensate for that fact when they were running tests. However, it wasn't all that they wrote about. In the amber substance was faint traces of blood, but DNA tests haven't been conclusive either. Results from the incisor were nil and the flesh pulled from the beetle was indeed human, results again nil. The flesh itself came from inside the mouth, specifically from the cheek.
Grissom had a hand under his chin as he continued to read. The flesh wasn't fresh nor was it rotting, in fact, it was preserved. But it wasn't preserved with the usual suspects, it was preserved by something else and once more the technicians couldn't identify what it was. Grissom shook his head, "Preserved flesh found in a beetle what does it mean?
He glanced over to the raven that quietly sat on the swing. His theory formulated and while he still looked at the raven, he moved his hand to the container and pushed open a slider that exposes minute holes that allowed air to pass through the container. Almost immediately the raven turned its head toward the container and begun to react violently. Its talons smacked against the birdcage, rattling them as the raven tried to push its head through the side. Grissom turned his head to the beetles and said, "The raven eats the beetle and the raven becomes… a part of me."
Grissom closed the slider and the raven quieted down. As he stared at the beetles, Grissom said, "They are me and I am they, for we are Legion."
Nick came into his office and sees Grissom staring at the beetles. Grissom broke from his stare and turned to Nick, "What is it?"
"I heard a noise, is everything okay?" Nick asked him. Grissom nodded, "I figured it out."
"You did?" Nick walked to his desk. Grissom pointed behind to the raven, "The beetles are attracting ravens with their pheromone."
"You're saying the beetles want to be eaten?" Nick blinked. Grissom nodded. Nick asked, "Why would they want to be eaten?"
"You should be asking me, why the beetles would only attract ravens," Grissom told him. Nick nodded and cleared his throat. "Why the beetles would only attract ravens?" he asked instead. Grissom raised a finger, "I don't know. I only found remnants of beetles in raven nests. The pheromones don't affect us—humans—or else we'd hear something about it. No dogs or cats ate the beetles so there's that."
"But then, wouldn't the beetles attract other species of birds related to the raven?" Nick asked him. Grissom sighed then looked up to Nick. "Doesn't Joey have a pet bluebird?"
"Yeah, Cree, he keeps him in his office," Nick remembered. Grissom pointed at him, "Get Cree in here. I want to test another theory."
"I don't think Joey would let me borrow Cree," Nick shook his head. Grissom rolled his eyes, "It's a matter of life and death. You can tell him I made you, now hurry up."
Nick hurried out of the office and Grissom rubbed his eyes. He looked at the beetles, "What are you planning?"
In a few minutes Nick returned with Cree's birdcage, behind him was Joey with a befuddled look. "Explain to me why Nick bird-napped my Cree?" Joey asked Grissom. Grissom looked at him, "The beetles' pheromones are only attracting ravens. I had a theory that if true, why haven't we seen any other birds with amber eyes?"
"Okay, I'll bite, what do you think?" Joey tilted his head as Nick rested the birdcage gently on Grissom's desk. Grissom sighed, "Wouldn't the beetles affect other species of birds that belong to Corvus?"
"In theory, they should," Joey blinked. Grissom carefully pushed on the slider, exposing the minute holes again. Once more the raven became increasingly agitated and begun to attack the birdcage. The bluebird didn't respond at all; abet only responding to the raven's reactions. When Grissom shut the slider closed, the raven calmed down again and became docile. Joey and Nick were in awe and Grissom looked at the bluebird.
"I don't understand, Cree should've been off its rocker too," Nick professed. Joey nodded. Grissom rubbed his beard, "I think the pheromones are only capable of attracting ravens."
"But, how would that be possible?" Nick asked. Joey shrugged, "Unless the beetles can change their pheromones."
Grissom pointed at Joey, "That's the idea."
"But, Grissom, that could only happen if someone specifically engineered the beetles," Nick looked at him. Joey looked at Nick, "Are you crazy? Like a big hulking thing can produce engineered beetles specifically to be eaten by ravens."
"Even then, why would anyone engineer beetles at all?" Nick questioned. Joey sighed, "And what would be the reason?"
"Because, I think our dear friend is hiding something more under that mask of his," Grissom sat back in his seat as he looked at the beetles.