"Inside the gleaming domes of Mars Colony One, seventeen-year-old Lizzy Engram and her fellow cadets work to make the Red Planet habitable. And every Sunday night, the doctors erase their memories. Week by week the procedure is carried out. Until one morning Lizzy wakes with all of the missing memories inside her head. And not just her own, but the memories of every cadet on the planet--from the boy who falls in love with her every week, to the girl who wants to ruin her life, to the cadets who have simply disappeared. Now ... Lizzy has six days to figure out what the doctors are hiding--and why--or she'll lose more than her memories."--