Afteranightoutofpartyingandleftbehindbyherfriends,Avawakesupandsneaksbackhomeonlytofindthatshe'salreadysafeinbed.Butthat'snotAva-it'ssomeonewholooksjustlikeher.Atime-travelingfugitivehasstolenAva'sbody,heridentity,andherlife.What'smore--she'snotalone.Thereareothers,hidinginthepast,secretlylivingamongus,plottingtoalterthefuture.Withoutherbody,Avaisavirtualghost,silentandinvisibletotheworld.And,sofarassheknows,she'stheonlyonewhocanstopthemandputthetimelinebackoncourse....