The heads of Cerberus
(Book)

Philadelphia, 1918: Three friends-brave, confident Viola Trenmore, clever but shy Robert Drayton, and Viola's strong and hot-tempered brother, Terry-discover a mysterious powder that transports them two hundred years into the future. The Philadelphia of 2118 is no longer a bustling metropolis but instead a completely isolated city recovering from an unknown disaster. Citizens are issued identification tags instead of having names, and society is split between a wealthy, powerful minority and a downtrodden lower class. The position of supreme authority is held by a woman, and once a year she oversees competitions to the death to determine who rules alongside her. When Viola, Terry, and Robert are forced to take part in these strange and deadly games, it will take their combined wits for them to escape this strange world and return home. -- from Amazon.