Zilpha Keatley Snyder

The first time Melanie Ross meets April Hall, she's not sure they have anything in common. But she soon discovers that they both love anything to do with ancient Egypt. When they stumble upon a deserted storage yard, Melanie and April decide it's the perfect spot for the Egypt Game. Before long there are six Egyptians, and they all meet to wear costumes, hold ceremonies, and work on their secret code. Everyone thinks it's just a game until strange...

In 1938, twelve-year-old William has already decided to leave home when his younger sister informs him that she and their brother and sister are going too, and right away, but complications arise when an acquaintance decides to "help" them.