Due to his hyperthymesia David has never been able to stand crowds, and so once he grew up he moved out to a quiet village in the mountains. He's only spent about a third of his life in an urban environment.
Atlantis: Ocean in the Age of Titans
David arrives at Area 51, the only area exempt from the bleaching. After entering and digging through the archives, he learns about an alien lifeform being contained in that area. After reading about what happened to the creature, Bluebook assumes the alien invasion was mankind's fault, but then he wonders if that's the whole truth. He decided to head to the secret section to verify the claims about the alien. After spending some time searching, he finally managed to find the door, and using his remaining strength, he managed to open it only to find a room not very different from the ones he had found before, with the exception there was a medical examination table where it rested what looked like a dead tree. Before he could examine it, another person in the room, pointing him with a gun, tells him he was waiting for him before shooting him.
David has hyperthymesia, which lets him perfectly recall memories down to the smallest detail as if they were right next to him in the present. It drove him insane as a kid, causing him to hate cities and people. His friends saw it as a disability and sympathized with him, while doctors considered it a gift.