In The Castle in the Sky, Allos is a high school student whose life suddenly changes after reading an e-mail. He finds out that there's so much more to the e-mail than its mere words. He comes across people that he has never seen before and goes on an adventure that he has never thought he would be on. The journey is a long and dangerous one, but with the help of his new friends, he has to piece together the clues to a mystery so that he can get his life back again.