"That specific dragon was... different..." the scientist wrung her hands. "You see, dragons are categorized in a specific way. First, based off of their physical structure and wings, then their scale color, then their size, then their magical capabilities, then their intelligence/ eye color. This dragon was just a small Standing White Dragon. Can't even produce elemental magical breath... the only thing special about this dragon is it's intelligence and..." 

She seemed ready to throw up. 

"...oh, I thought it was properly secure. You see, this dragon is so intelligent that it can communicate with humans. So it blends in perfectly... especially since this dragon can shape shift. He could literally be anyone in this room. He's either long gone, or he's knocked out someone and taken their place. Of course, he wouldn't leave without freeing the other dragons! Oh no! What are we going to do?"