"Annabeth, calm down." The guy with the jet-black hair says. "They are here for a reason. I invited them. But first, a formal introduction. Welcome to Camp Half-Blood." 

Ginny's eyes almost bug out of her head. 

"Ginny-"I begin to say, but she cuts me off, practically yelling at the black haired guy. 

"What do you mean, you invited us?? We got a tip from a man on the street, with black hair-" She takes a breath, then begins again, but this tume in a quieter voice. "Oh. That was you. But, How? You did not look like that."

"There is such things as disguises, you know." he says. "Besides, you wouldn't have realized, because you weren't looking for me, or expecting you would ever see me again."

"B-b-but!" Ginny splutters. "How did you get here before us? There was the same amount of traffic."

"One, I already had my ride ready, and you had to hail two cabs, two, I already had a back route planned, and three, I went the back way which is faster, and you wouldn't see me arrive." He said.

"OK, but how do we know we can trust you?" Bill said.

"Because I need your help." The guy says. "But first, we need to get acquainted, and you need to a) settle in, and b) either tell your guardians where you are and have them come here, or tell them where you are and have them not come. Your choice." He smirks. "But if you bring them here, I'm not guaranteeing that they will be able to see this place as more than a plot of empty land."

"Is that why the cabbie couldn't see this place?" Harry asked.

"Yes." The girl called Annabeth said. "Camp Half-Blood, as well as many other places, are protected by the Mist, making mere mortals unable to see them. They are often disguised as regular places."

"What are your accents?" Ron butted in.

"I was going to ask you the same thing." The girl said. "I was born in California, but moved here when I was 7. So I highly doubt you would catch my 'Californian accent.'"

"Well, we are from Britain. And I am an official in the Ministry of Magic, and I've never heard of this place or the so-called Mist. And being in the Ministry of Magic means that I know a lot, so if I don't know this place, that's saying something." Percy said in a very agitated voice.

"Percy, calm down." Charlie said. "Give it a rest."

"Wait, your name is Percy?" The black haired guy said. "That's-"

"Later." Annabeth said. "But now, let's get them situated. And once again, whoever you are, welcome to Camp Half-Blood."